CY -abbr

  1. calendar year

cy·an ['sī-,an, -ən] -n

  1. a greenish-blue color used in photography and color printing of one of the primary colors

cyan- -comb form

  1. dark blue : blue
    • cyano bacterium
  2. cyanogen
    • cyan ide
  3. cyanide
    • cyano genetic

cy·an·a·mide [sī-'a-nə-məd] -n

  1. a caustic acidic compound CH 2N 2
  2. calcium cyanamide

cy·a·nate ['sī-ə-,nāt, -nət] -n

  1. a salt (as ammonium cyanate) or ester of cyanic acid

cy·an·ic acid [sī-'a-nik-] -n

  1. a strong acid HOCN used to prepare cyanates

cy·a·nide ['sī-ə-,nīd, -nəd] -n

  1. : a compound of cyanogen with a more electropositive element or group: as
  2. potassium cyanide
  3. sodium cyanide
  4. cyanogen

cy·a·nine ['sī-ə-,nēn, -nən] -n

  1. any of various dyes used esp. to sensitize photographic film to light from the green, yellow, red, and infrared regions of the spectrum

cy·a·no ['sī-ə-(,)nō, sī-'a-(,)nō] -adj

  1. relating to or containing the cyanogen group

cy·a·no·ac·ry·late [,sī-ə-nō-'a-krə-,lāt, sī-,a-nō-] -n

  1. any of several liquid acrylate monomers that readily polymerize as anions and are used as adhesives in industry and in closing wounds in surgery

cy·a·no·bac·te·ri·um [-bak-'tir-ē-əm] -n

  1. any of a major group (Cyanobacteria) of photosynthetic bacteria that have two photosystems, produce molecular oxygen, and use water as an electron-donating substrate in photosynthesis called also blue-green alga

cy·a·no·co·bal·a·min [-kō-'ba-lə-mən] -n

  1. vitamin b 12

cy·an·o·gen [sī-'a-nə-jən] -n

  1. a monovalent group CN present in cyanides
  2. a colorless flammable poisonous gas (CN) 2

cy·a·no·ge·net·ic [,sī-ə-nō-jə-'ne-tik, sī-,a-nō-] -adj, n

  1. capable of producing cyanide (as hydrogen cyanide)
    • a cyanogenetic glucoside

cy·a·no·hy·drin [-'hī-drən] -n

  1. any of various compounds containing both cyano and hydroxyl groups

cy·a·no·sis [,sī-ə-'nō-səs] -n, adj

  1. a bluish or purplish discoloration (as of skin) due to deficient oxygenation of the blood

cy·an·uric acid [,sī-ə-'nu̇r-ik-, -'nyu̇r-] -n

  1. a crystalline weak acid C 3N 3(OH) 3that yields cyanic acid when heated

Cyb·e·le ['si-bə-(,)lē] -n

  1. a nature goddess of the ancient peoples of Asia Minor

cy·ber ['sī-bər] -adj

  1. of, relating to, or involving computers or computer networks (as the Internet)
    • the cyber marketplace

cyber- -comb form

  1. computer : computer network
    • cyber space

cy·ber·ca·fe ['sī-bər-ka-'fā] -n

  1. a cafe or coffee shop providing computers for access to the Internet

cy·ber·cit·i·zen [-'si-tə-zən] -n

  1. netizen

cy·ber·na·tion [,sī-bər-'nā-shən] -n, adj

  1. the automatic control of a process or operation (as in manufacturing) by means of computers

cy·ber·naut ['sī-bər-,nȯt, -nät] -n

  1. netizen

cy·ber·ne·ti·cian [,sī-(,)bər-nə-'ti-shən] -n

  1. a specialist in cybernetics

cy·ber·net·i·cist [,sī-bər-'ne-tə-sist] -n

  1. cybernetician

cy·ber·net·ics [,sī-bər-'ne-tiks] -n pl but sing in constr, adj, adv

  1. the science of communication and control theory that is concerned esp. with the comparative study of automatic control systems (as the nervous system and brain and mechanical-electrical communication systems)

cy·ber·porn ['sī-bər-,pȯrn] -n

  1. pornography accessible online esp. via the Internet

cy·ber·punk ['sī-bər-,pəŋk] -n

  1. science fiction dealing with future urban societies dominated by computer technology
  2. an opportunistic computer hacker

cy·ber·se·cu·ri·ty [-si-,kyu̇r-ə-tē] -n

  1. measures taken to protect a computer or computer system (as on the Internet) against unauthorized access or attack

cy·ber·sex [-,seks] -n

  1. online sex-oriented conversations and exchanges
  2. sex-oriented material available on a computer

cy·ber·space [-,spās] -n

  1. the online world of computer networks and esp. the Internet

cy·ber·speak [-,spēk] -n

  1. jargon relating to or used in online communications

cy·ber·surf·er [-,sər-fər] -n

  1. one who surfs the Internet

cy·ber·ter·ror·ism [-,ter-ər-,i-zəm] -n

  1. terrorist activities intended to damage or disrupt vital computer systems

cy·borg ['sī-,bȯrg] -n

  1. a bionic human

cy·brar·ian [sī-'brer-ē-ən, -'bre-rē-] -n

  1. a person whose job is to find, collect, and manage information that is available on the World Wide Web

cy·cad ['sī-kəd] -n

  1. any of an order (Cycadales) of dioecious cycadophytes that flourished esp. during the Jurassic and are represented by four surviving families of palmlike tropical plants

cy·cad·e·oid [sī-'ka-dē-,ȯid] -n

  1. any of a division (Cycadeoidophyta syn. Bennettitophyta) of extinct Jurassic to Cretaceous gymnosperms that differ from the cycadophytes chiefly in having the reproductive organs on the trunk embedded in a thick covering of bracts and scales

cy·cad·o·phyte [sī-'ka-də-,fīt] -n

  1. any of a division (Cycadophyta) of usu. unbranched mostly extinct gymnosperms with pinnate leaves, large pith, little xylem, and a thick cortex that includes the cycads, cycadeoids, and seed ferns

cy·ca·sin ['sī-kə-sən] -n

  1. a glucoside C 8H 16N 2O 7that occurs in cycads and results in toxic and carcinogenic effects when introduced into mammals

cycl- -comb form

  1. circle
    • cyclo meter
  2. cyclic
    • cyclo hexane

cy·cla·mate ['sī-klə-,māt, -mət] -n

  1. an artificially prepared salt of sodium or calcium used esp. formerly as a sweetener

cy·cla·men ['sī-klə-mən, 'si-] -n

  1. any of a genus ( Cyclamen) of Old World plants of the primrose family having showy nodding flowers

cy·clase ['sī-,klās, -,klāz] -n

  1. an enzyme (as adenylate cyclase) that catalyzes cyclization of a compound

cy·claz·o·cine [sī-'kla-zə-,sēn, -sən] -n

  1. an analgesic drug C 18H 25NO that inhibits the effect of morphine and related addictive drugs and is used in the treatment of drug addiction

cy·cle ['sī-kəl] -n

  1. an interval of time during which a sequence of a recurring succession of events or phenomena is completed
    • a 4-year cycle of growth and development
  2. a course or series of events or operations that recur regularly and usu. lead back to the starting point
  3. one complete performance of a vibration, electric oscillation, current alternation, or other periodic process
  4. a permutation of a set of ordered elements in which each element takes the place of the next and the last becomes first
  5. a takeoff and landing of an airplane
  6. : a circular or spiral arrangement: as
  7. an imaginary circle or orbit in the heavens
  8. ring
  9. a long period of time : age
  10. a group of creative works (as poems, plays, or songs) treating the same theme
  11. a series of narratives dealing typically with the exploits of a legendary hero
  12. bicycle
  13. tricycle
  14. motorcycle
  15. the series of a single, double, triple, and home run hit in any order by one player during one baseball game

cycle ['sī-k(ə-)liŋ] -vb, n

  1. to pass through a cycle
  2. to recur in cycles
  3. to ride a cycle
  4. bicycle
  5. to cause to go through a cycle

cy·cle·way [-,wā] -n

  1. bikeway

cy·clic ['sī-klik also 'si-] -adj, adv

  1. of, relating to, or being a cycle
  2. moving in cycles
    • cyclic time
  3. of, relating to, or being a chemical compound containing a ring of atoms
  4. being a mathematical group that has an element such that every element of the group can be expressed as one of its powers

cyclic AMP -n

  1. a cyclic mononucleotide of adenosine that is formed from ATP and is responsible for the intracellular mediation of hormonal effects on various cellular processes called also adenosine 3,5-monophosphate

cyclic GMP [-,jē-(,)em-'pē] -n

  1. a cyclic mononucleotide of guanosine that acts similarly to cyclic AMP as a secondary messenger in response to hormones

cy·clic·i·ty [sī-'kli-sə-tē, si-] -n

  1. the quality or state of being cyclic
    • estrous cyclicity
    called also cy*cli*cal*i*ty si-kl-ka-l-te, si-

cy·clin ['sī-klən, 'si-] -n

  1. any of a group of proteins active in controlling the cell cycle and in initiating DNA synthesis

cy·clist ['sī-k(ə-)ləst] -n

  1. one who rides a cycle

cy·cli·tol ['sī-klə-,tȯl, 'si-, -,tōl] -n

  1. an alicyclic polyhydroxy compound (as inositol)

cy·cli·za·tion [,sī-k(ə-)lə-'zā-shən, ,si-] -n, vb

  1. formation of a ring in a chemical compound

cy·clo ['sē-(,)klō, 'si-] -n

  1. a 3-wheeled often motor-driven taxi

cy·clo·ad·di·tion [,sī-(,)klō-ə-'di-shən] -n

  1. a chemical reaction leading to ring formation in a compound

cy·clo·al·i·phat·ic [,sī-klō-,a-lə-'fa-tik] -adj

  1. alicyclic

cy·clocross ['sī-klə-,krȯs, -klō-] -n

  1. the sport of racing bicycles over rough terrain that usu. requires carrying the bicycle over obstacles

cy·clo·dex·trin [-'dek-strən] -n

  1. any of a class of complex cyclic sugars that are products of the enzymatic decomposition of starch and that can catalyze reactions between simpler molecules which come together within the cylindrical body of the sugar

cy·clo·di·ene [-'dī-,ēn, -dī-'] -n

  1. an organic insecticide (as dieldrin or chlordane) with a chlorinated methylene group forming a bridge across a 6-membered carbon ring

cy·clo·gen·e·sis [-'je-nə-səs] -n

  1. the development or intensification of a cyclone

cy·clo·hex·ane [,sī-klō-'hek-,sān] -n

  1. a pungent saturated cyclic hydrocarbon C 6H 12found in petroleum or made synthetically and used chiefly as a solvent and in organic synthesis

cy·clo·hex·a·none [-'hek-sə-,nōn] -n

  1. a liquid ketone C 6H 10O used esp. as a solvent and in organic synthesis

cy·clo·hex·i·mide [-'hek-sə-,mīd, -məd] -n

  1. an agricultural fungicide C 15H 23NO 4that inhibits protein synthesis and is obtained from a soil bacterium ( Streptomyces griseus)

cy·clo·hex·yl·amine [-hek-'si-lə-,mēn] -n

  1. a colorless liquid amine C 6H 11NH 2that is used in organic synthesis and to prevent corrosion in boilers and that is believed to be harmful as a metabolic breakdown product of cyclamate

cy·cloid ['sī-,klȯid] -n, adj

  1. a curve that is generated by a point on the circumference of a circle as it rolls along a straight line

cycloid -adj

  1. smooth with concentric lines of growth
    • cycloid scales
  2. having or consisting of cycloid scales
  3. characterized by alternating high and low moods
    • a cycloid personality

cy·clom·e·ter [sī-'klä-mə-tər] -n

  1. a device made for recording the revolutions of a wheel and often used for registering distance traversed by a wheeled vehicle

cy·clone ['sī-,klōn] -n, adj, adv

  1. a storm or system of winds that rotates about a center of low atmospheric pressure, advances at a speed of 20 to 30 miles (about 30 to 50 kilometers) an hour, and often brings heavy rain
  2. tornado
  3. low
  4. any of various centrifugal devices for separating materials (as solid particles from gases)

Cy·clone ['sī-,klōn] -trademark

  1. used for a chain-link fence

cyclone cellar -n

  1. storm cellar

cy·clo·ole·fin [,sī-klō-'ō-lə-fən] -n, adj

  1. a hydrocarbon containing a ring having one or more double bonds

cy·clo·ox·y·gen·ase [-'äk-si-jə-,nās] -n

  1. an enzyme that catalyzes the conversion of arachidonic acid to prostaglandins and that has two isoforms of which one is involved in the creation of prostaglandins which mediate inflammation and pain

cy·clo·par·af·fin [-'per-ə-fən, -'pa-rə-] -n

  1. a saturated cyclic hydrocarbon of the formula C n H 2 n

cy·clo·pe·an [,sī-klə-'pē-ən, sī-'klō-pē-] -adj

  1. of, relating to, or characteristic of a Cyclops
  2. huge, massive
  3. of or relating to a style of stone construction marked typically by the use of large irregular blocks without mortar

cy·clo·pe·dia [,sī-klə-'pē-dē-ə] -n, adj

  1. encyclopedia

cy·clo·phos·pha·mide [,sī-klō-'fäs-fə-,mīd] -n

  1. an immunosuppressive and antineoplastic agent C 7H 15Cl 2N 2O 2P used esp. in the treatment of lymphomas and some leukemias

cy·clo·pro·pane [,sī-klə-'prō-,pān] -n

  1. a flammable gaseous saturated cyclic hydrocarbon C 3H 6sometimes used as a general anesthetic

cy·clops ['sī-,kläps] -n

  1. any of a race of giants in Greek mythology with a single eye in the middle of the forehead
  2. any of a genus ( Cyclops) of freshwater predatory copepods having a single median eye

cy·clo·ra·ma [,sī-klə-'ra-mə, -'rä-] -n, adj

  1. a large pictorial representation encircling the spectator and often having real objects as a foreground
  2. a curved curtain or wall used as a background of a stage set to suggest unlimited space

cy·clo·ser·ine [,sī-klō-'ser-,ēn] -n

  1. a broad-spectrum antibiotic C 3H 6N 2O 2produced by an actinomycete ( Streptomyces orchidaceus) and used esp. in the treatment of tuberculosis

cy·clo·sis [sī-'klō-səs] -n

  1. the streaming of protoplasm within a cell

cy·clo·spo·ra [,sī-klō-'spȯr-ə] -n

  1. any of a genus ( Cyclosporaof the order Coccidia) of sporozoans including one ( C. cayetanensis) causing diarrhea in humans

cy·clo·spor·ine [,sī-klə-'spȯr-ᵊn, -,ēn] -n

  1. an immunosuppressive polypeptide drug C 62H 111N 11O 12obtained from various imperfect fungi and used esp. to prevent rejection of organ transplants

cy·clo·stome ['sī-klə-,stōm] -n

  1. any of a class (Cyclostomata) of jawless fishes having a large sucking mouth and comprising the hagfishes and lampreys

cy·clo·style [-,stī(-ə)l] -n, vt

  1. a machine for making multiple copies that utilizes a stencil cut by a graver whose tip is a small rowel

cy·clo·thy·mic [,sī-klə-'thī-mik] -adj, n

  1. relating to or being a mood disorder characterized by alternating episodes of depression and elation in a form less severe than that of bipolar disorder

cy·clo·tom·ic [-'tä-mik] -adj

  1. relating to, being, or containing a polynomial of the form x p 1 x p 2... x 1 where pis a prime number

cy·clo·tron ['sī-klə-,trän] -n

  1. an accelerator in which charged particles (as protons, deuterons, or ions) are propelled by an alternating electric field in a constant magnetic field

cy·der ['sī-dər] -n

(variant of cider)

  1. fermented apple juice often made sparkling by carbonation or fermentation in a sealed container
  2. the expressed juice of fruit (as apples) used as a beverage or for making other products (as applejack)

cyg·net ['sig-nət] -n

  1. a young swan

Cyg·nus ['sig-nəs] -n

  1. a northern constellation between Lyra and Pegasus in the Milky Way

cyl -abbr

  1. cylinder

cyl·in·der ['si-lən-dər] -n, adj

  1. the surface traced by a straight line moving parallel to a fixed straight line and intersecting a fixed planar closed curve
  2. a solid or surface bounded by a cylinder and two parallel planes cutting all its elements
  3. right circular cylinder
  4. : a cylindrical body or space: as
  5. the turning chambered breech of a revolver
  6. the piston chamber in an engine
  7. a chamber in a pump from which the piston expels the fluid
  8. any of various rotating members in a press (as a printing press)
  9. one that impresses paper on an inked form
  10. a cylindrical clay object inscribed with cuneiform inscriptions

cylinder head -n

  1. the closed end of an engine or pump cylinder

cylinder seal -n

  1. a cylinder (as of stone) engraved in intaglio and used esp. in ancient Mesopotamia to roll an impression on wet clay

cy·lin·dri·cal [sə-'lin-dri-kəl] -adj, adv

  1. relating to or having the form or properties of a cylinder

cylindrical coordinate -n

  1. any of the coordinates in space obtained by constructing in a plane a polar coordinate system and on a line perpendicular to the plane a linear coordinate system

cy·ma ['sī-mə] -n

  1. a projecting molding whose profile is an S-shaped curve
  2. an S-shaped curve formed by the union of a concave line and a convex line

cy·ma·tium [sī-'mā-sh(ē-)əm] -n

  1. a crowning molding in classic architecture
  2. cyma

cym·bal ['sim-bəl] -n

  1. a concave brass plate that produces a brilliant clashing tone and that is struck with a drumstick or is used in pairs struck glancingly together

cym·bid·i·um [sim-'bi-dē-əm] -n

  1. any of a genus ( Cymbidium) of tropical Old World epiphytic orchids with showy flowers

cyme ['sīm] -n

  1. an inflorescence in which each floral axis terminates in a single flower
  2. a determinate inflorescence of this type containing several flowers with the first-opening central flower terminating the main axis and subsequent flowers developing from lateral buds

cym·ling ['sim-lən, -liŋ] -n

  1. pattypan

cy·mo·phane ['sī-mə-,fān] -n

  1. chrysoberyl
  2. an opalescent chrysoberyl

cy·mose ['sī-,mōs] -adj

  1. of, relating to, being, or bearing a cyme

Cym·ric ['kəm-rik, 'kim-] -adj

  1. of, relating to, or characteristic of the non-Gaelic Celtic people of Britain or their language
  2. welsh

Cymric -n

  1. brythonic
  2. the Welsh language

Cym·ry [-rē] -n

  1. welsh

cyn·ic ['si-nik] -n, adj

  1. an adherent of an ancient Greek school of philosophers who held the view that virtue is the only good and that its essence lies in self-control and independence
  2. a faultfinding captious critic
  3. one who believes that human conduct is motivated wholly by self-interest

cyn·i·cal ['si-ni-kəl] -adj, adv

  1. captious, peevish
  2. : having or showing the attitude or temper of a cynic: as
  3. contemptuously distrustful of human nature and motives
    • those cynical men who say that democracy cannot be honest and efficient -- F. D. Roosevelt
  4. based on or reflecting a belief that human conduct is motivated primarily by self-interest
    • a cynical ploy to cheat customers

cyn·i·cism ['si-nə-,si-zəm] -n

  1. the doctrine of the Cynics
  2. cynical character, attitude, or quality
  3. an expression of such quality

cy·no·mol·gus monkey [,sī-nə-'mäl-gəs-] -n

  1. a macaque ( Macaca fascicularis) of southeastern Asia, Borneo, and the Philippines that sometimes feeds on marine crustaceans and shellfish and is often used in medical research

cy·no·sure ['sī-nə-,shu̇r, 'si-] -n

  1. the northern constellation Ursa Minor
  2. north star
  3. one that serves to direct or guide
  4. a center of attraction or attention
    • turned an eyesore into a cynosure -- Catherine Reynolds

Cyn·thia ['sin(t)-thē-ə] -n

  1. artemis
  2. the moon personified as a goddess

CYO -abbr

  1. Catholic Youth Organization

cy·pher ['sī-fər] -n

(variant of cipher)

  1. zero
  2. one that has no weight, worth, or influence : nonentity
  3. a method of transforming a text in order to conceal its meaning
  4. a message in code
  5. arabic numeral
  6. a combination of symbolic letters
  7. the interwoven initials of a name

cy pres [,sī-'prā, ,sē-] -n

  1. a rule providing for the interpretation of instruments in equity as nearly as possible in conformity to the intention of the testator when literal construction is illegal, impracticable, or impossible called also cy pres doctrine
  2. in accordance with the rule of cy pres

cy·press ['sī-prəs] -n

  1. any of a genus ( Cupressusof the family Cupressaceae, the cypress family) of evergreen trees and shrubs with small overlapping leaves resembling scales
  2. any of several coniferous trees of the cypress family or the bald cypress family
  3. bald cypress
  4. the wood of a cypress tree
  5. branches of cypress used as a symbol of mourning

cypress -n

  1. a silk or cotton usu. black gauze formerly used for mourning

cypress vine -n

  1. a tropical American annual vine ( Ipomoea quamoclitsyn. Quamoclit pennata) of the morning-glory family with usu. red or white tubular flowers and finely dissected leaves

cyp·ri·an ['si-prē-ən] -n

  1. prostitute

cyp·ri·nid ['si-prə-nəd] -n, adj

  1. any of a family (Cyprinidae) of soft-finned freshwater fishes including the carps and minnows

cyp·ri·pe·di·um [,si-prə-'pē-dē-əm] -n

  1. any of a genus ( Cypripedium) of Eurasian and No. American terrestrial orchids having large usu. showy drooping flowers with the lip inflated or pouched
  2. any of a genus ( Paphiopedalum) of widely cultivated Asian orchids

cy·pro·hep·ta·dine [,sī-prō-'hep-tə-,dēn] -n

  1. a histamine and serotonin antagonist C 21H 21N used esp. in the form of its hydrochloride to treat allergy symptoms and hives

cy·prot·er·one [sī-'prä-tə-,rōn] -n

  1. a synthetic steroid C 22H 27ClO 3that inhibits androgenic secretions (as of testosterone)

Cy·re·na·ic [,sir-ə-'nā-ik, ,sī-rə-] -n, adj

  1. an adherent of the doctrine that pleasure is the chief end of life

Cy·ril·lic [sə-'ri-lik] -adj

  1. of, relating to, or constituting an alphabet used for writing Old Church Slavic and for Russian and a number of other languages of eastern Europe and Asia

cyst ['sist] -n

  1. a closed sac having a distinct membrane and developing abnormally in a cavity or structure of the body
  2. : a body resembling a cyst: as
  3. a resting spore of many algae
  4. a gas-filled vesicle (as of a rockweed or bladderwort)
  5. a capsule formed about a minute organism going into a resting or spore stage
  6. this capsule with its contents
  7. a resistant cover about a parasite produced by the parasite or the host

cyst- -comb form

  1. bladder
    • cyst itis
    : sac
    • cysto carp

cys·te·amine [sis-'tē-ə-mən] -n

  1. a cysteine derivative C 2H 7NS used esp. to treat cystinuria

cys·te·ine ['sis-tə-,ēn] -n

  1. a crystalline sulfur-containing amino acid C 3H 7NO 2S readily oxidizable to cystine

cys·tic ['sis-tik] -adj

  1. of or relating to the urinary bladder or the gallbladder
  2. relating to, composed of, or containing cysts
  3. enclosed in a cyst

cys·ti·cer·coid [,sis-tə-'sər-,kȯid] -n

  1. a tapeworm larva having an invaginated scolex and solid tailpiece

cys·ti·cer·co·sis [,sis-tə-(,)sər-'kō-səs] -n

  1. infestation with or disease caused by cysticerci

cys·ti·cer·cus [-'sər-kəs] -n

  1. a tapeworm larva that consists of a fluid-filled sac containing an invaginated scolex and is situated in the tissues of an intermediate host

cystic fibrosis -n

  1. a hereditary disease esp. among whites that appears usu. in early childhood, is inherited as an autosomal recessive trait, involves functional disorder of the exocrine glands, and is marked esp. by faulty digestion due to a deficiency of pancreatic enzymes, by difficulty in breathing due to mucus accumulation in airways, and by excessive loss of salt in the sweat

cys·tine ['sis-,tēn] -n

  1. a crystalline amino acid C 6H 12N 2O 4S 2that is widespread in proteins (as keratins) and is a major metabolic sulfur source

cys·tin·uria [,sis-tə-'nu̇r-ē-ə, -'nyu̇r-] -n

  1. a metabolic defect characterized by excretion of excessive amounts of cystine in the urine and inherited as an autosomal recessive trait

cys·ti·tis [sis-'tī-təs] -n

  1. inflammation of the urinary bladder

cys·to·lith ['sis-tə-,lith] -n

  1. a calcium carbonate concretion arising from the cellulose wall of cells of higher plants

cys·to·scope ['sis-tə-,skōp] -n, adj

  1. a rigid endoscope for inspecting and passing instruments into the urethra and bladder

cyt- -comb form

  1. cell
    • cyto logy
  2. cytoplasm
    • cyto kinesis

Cyth·er·ea [,si-thə-'rē-ə] -n

  1. aphrodite

Cyth·er·e·an [-'rē-ən] -adj

  1. of or relating to the planet Venus

cy·ti·dine ['si-tə-,dēn, 'sī-] -n

  1. a nucleoside containing cytosine

cy·to·cha·la·sin [,sī-tō-kə-'lā-sən] -n

  1. any of a group of metabolites isolated from fungi (esp. Helminthosporium dematioideum) that inhibit various cell processes

cy·to·chem·is·try [-'ke-mə-strē] -n, adj

  1. microscopic biochemistry
  2. the chemistry of cells

cy·to·chrome ['sī-tə-,krōm] -n

  1. any of several intracellular hemoprotein respiratory pigments that are enzymes functioning in electron transport as carriers of electrons

cytochrome c -n

  1. the most abundant and stable of the cytochromes

cytochrome oxidase -n

  1. an iron-porphyrin enzyme important in cell respiration due to its ability to catalyze the oxidation of reduced cytochrome c in the presence of oxygen

cy·to·dif·fer·en·ti·a·tion ['sī-tō-,di-fə-,ren(t)-shē-'ā-shən] -n

  1. the development of specialized cells (as muscle, blood, or nerve cells) from undifferentiated precursors

cy·to·ge·net·ics [,sī-tō-jə-'ne-tiks] -n pl but sing or pl in constr, adj, adv, n

  1. a branch of biology that deals with the study of heredity and variation by the methods of both cytology and genetics

cy·to·kine ['sī-tə-,kīn] -n

  1. any of a class of immunoregulatory proteins (as interleukin or interferon) that are secreted by cells esp. of the immune system

cy·to·ki·ne·sis [,sī-tō-kə-'nē-səs, -kī-] -n, adj

  1. the cytoplasmic changes accompanying mitosis
  2. cleavage of the cytoplasm into daughter cells following nuclear division

cy·to·ki·nin [,sī-tə-'kī-nən] -n

  1. any of various plant growth substances (as kinetin) that are usu. derivatives of adenine

cytol -abbr

  1. cytological; cytology

cy·tol·o·gy [sī-'tä-lə-jē] -n, adj, adv

  1. a branch of biology dealing with the structure, function, multiplication, pathology, and life history of cells
  2. the cytological aspects of a process or structure

cy·to·ly·sin [,sī-tə-'lī-sᵊn] -n

  1. a substance (as an antibody that lyses bacteria) producing cytolysis

cy·tol·y·sis [sī-'tä-lə-səs] -n, adj

  1. the usu. pathologic dissolution or disintegration of cells

cy·to·me·gal·ic [,sī-tō-mi-'ga-lik] -adj

  1. characterized by or causing the formation of enlarged cells

cy·to·meg·a·lo·vi·rus [,sī-tə-,me-gə-lō-'vī-rəs] -n

  1. a herpesvirus (species Human herpesvirus 5of the genus Cytomegalovirus) that causes cellular enlargement and formation of eosinophilic inclusion bodies esp. in the nucleus and acts as an opportunistic infectious agent in immunosuppressed conditions (as AIDS)

cy·to·mem·brane [,sī-tō-'mem-,brān] -n

  1. one of the cellular membranes including those of the plasma membrane, endoplasmic reticulum, nuclear envelope, and Golgi apparatus
  2. unit membrane

cy·to·path·ic [,sī-tə-'pa-thik] -adj

  1. of, relating to, characterized by, or producing pathological changes in cells

cy·to·path·o·gen·ic [-,pa-thə-'je-nik] -adj, n

  1. pathologic for or destructive to cells

cy·to·pa·thol·o·gy [-pə-'thä-lə-jē, -pa-] -n

  1. a branch of pathology that deals with manifestations of disease at the cellular level

cy·to·phil·ic [,sī-tə-'fi-lik] -adj

  1. having an affinity for cells

cy·to·pho·tom·e·try [-fō-'tä-mə-trē] -n, adj

  1. photometry applied to the study of the cell or its constituents

cy·to·plasm ['sī-tə-,pla-zəm] -n, adj, adv

  1. the organized complex of inorganic and organic substances external to the nuclear membrane of a cell and including the cytosol and membrane-bound organelles (as mitochondria or chloroplasts)

cy·to·sine ['sī-tə-,sēn] -n

  1. a pyrimidine base C 4H 5N 3O that codes genetic information in the polynucleotide chain of DNA or RNA

cy·to·skel·e·ton [,sī-tə-'ske-lə-tən] -n, adj

  1. the network of protein filaments and microtubules in the cytoplasm that controls cell shape, maintains intracellular organization, and is involved in cell movement

cy·to·sol ['sī-tə-,säl, -,sȯl] -n, adj

  1. the fluid portion of the cytoplasm exclusive of organelles and membranes called also ground substance

cy·to·stat·ic [,sī-tə-'sta-tik] -adj, n

  1. tending to retard cellular activity and multiplication
    • cytostatic treatment of tumor cells

cy·to·tax·on·o·my [,sī-tō-(,)tak-'sä-nə-mē] -n, adj, adv

  1. study of the relationships and classification of organisms using both classical systematic techniques and comparative studies of chromosomes
  2. the nuclear cytologic makeup of a kind of organism

cy·to·tech·nol·o·gist [,sī-tə-tek-'nä-lə-jist] -n

  1. a medical technician trained in the identification of cells and cellular abnormalities (as in cancer)

cy·to·tox·ic [,sī-tə-'täk-sik] -adj, n

  1. of or relating to a cytotoxin
  2. toxic to cells
    • cytotoxic drugs

cytotoxic T cell -n

  1. killer t cell

cy·to·tox·in [-'täk-sən] -n

  1. a substance (as a toxin or antibody) having a toxic effect on cells