ox ['äks] -n

  1. a domestic bovine mammal ( Bos taurus)
  2. a bovine mammal
  3. an adult castrated male domestic ox

ox- -comb form

  1. oxygen
    • ox acillin

ox·a·cil·lin [,äk-sə-'si-lən] -n

  1. a semisynthetic penicillin administered in the form of its hydrated sodium salt C 19H 18N 3NaO 5SH 2O to treat infections caused by penicillin-resistant staphylococci

ox·a·late ['äk-sə-,lāt] -n

  1. a salt or ester of oxalic acid

ox·al·ic acid [(,)äk-'sa-lik-] -n

  1. a poisonous strong acid (COOH) 2or H 2C 2O 4that occurs in various plants (as spinach) as oxalates and is used esp. as a bleaching or cleaning agent and as a chemical intermediate

ox·al·is [äk-'sa-ləs] -n

  1. wood sorrel

ox·a·lo·ac·e·tate [,äk-sə-lō-'a-sə-,tāt] -n

  1. a salt or ester of oxaloacetic acid

ox·a·lo·ace·tic acid [,äk-sə-lō-ə-'sē-tik-] -n

  1. a crystalline acid C 4H 4O 5that is formed by reversible oxidation of malic acid (as in carbohydrate metabolism via the Krebs cycle) and in reversible transamination reactions (as from aspartic acid)

ox·a·lo·suc·cin·ic acid ['äk-sə-lō-sək-,si-nik-, äk-'sa-lō-] -n

  1. a tricarboxylic acid C 6H 6O 7that is formed as an intermediate in the Krebs cycle

ox·az·e·pam [äk-'sa-zə-,pam] -n

  1. a benzodiazepine tranquilizer C 15H 11ClN 2O 2

ox·blood ['äks-,bləd] -n

  1. a moderate reddish brown

ox·bow ['äks-,bō] -n, adj

  1. a U-shaped frame forming a collar about an ox's neck and holding the yoke in place
  2. something (as a bend in a river) resembling an oxbow

Ox·bridge ['äks-,brij] -adj

  1. of, relating to, or characteristic of Oxford and Cambridge Universities

ox·cart [-,kärt] -n

  1. a cart drawn by oxen

ox·eye [-,ī] -n

  1. any of several composite plants (as of the genera Chrysanthemumor Heliopsis) having heads with both disk and ray flowers
  2. daisy

oxeye daisy -n

  1. daisy

Oxfam -abbr

  1. Oxford Committee for Famine Relief

ox·ford ['äks-fərd] -n

  1. a low shoe laced or tied over the instep
  2. a soft durable cotton or synthetic fabric made in plain or basket weaves called also oxford cloth

Oxford down -n

  1. any of a Down breed of large hornless sheep developed by crossing Cotswolds and Hampshires called also Oxford

Oxford movement -n

  1. a High Church movement within the Church of England begun at Oxford in 1833

ox·heart ['äks-,härt] -n

  1. any of various large sweet cherries

ox·i·dant ['äk-sə-dənt] -n, adj

  1. oxidizing agent

ox·i·dase ['äk-sə-,dās, -,dāz] -n, adj

  1. any of various enzymes that catalyze oxidations
  2. one able to react directly with molecular oxygen

ox·i·da·tion [,äk-sə-'dā-shən] -n, adj, adv

  1. the act or process of oxidizing
  2. the state or result of being oxidized

oxidationreduction -n

  1. a chemical reaction in which one or more electrons are transferred from one atom or molecule to another

oxidation state -n

  1. a positive or negative number that represents the effective charge of an atom or element and that indicates the extent or possibility of its oxidation
    • the usual oxidation state of sodium is 1 and of oxygen 2
    called also oxidation number

oxidative phosphorylation -n

  1. the synthesis of ATP by phosphorylation of ADP for which energy is obtained by electron transport and which takes place in the mitochondria during aerobic respiration

ox·ide ['äk-,sīd] -n, adj

  1. a binary compound of oxygen with a more electropositive element or group

ox·i·dise ['äk-sə-,dīz] -vb, adj

(variant of oxidize)

  1. to combine with oxygen
  2. to dehydrogenate esp. by the action of oxygen
  3. to change (a compound) by increasing the proportion of the electronegative part or change (an element or ion) from a lower to a higher positive valence : remove one or more electrons from (an atom, ion, or molecule)
  4. to become oxidized

ox·i·dize ['äk-sə-,dīz] -vb, adj

  1. to combine with oxygen
  2. to dehydrogenate esp. by the action of oxygen
  3. to change (a compound) by increasing the proportion of the electronegative part or change (an element or ion) from a lower to a higher positive valence : remove one or more electrons from (an atom, ion, or molecule)
  4. to become oxidized

ox·i·diz·er [-,dī-zər] -n

  1. oxidizing agent
  2. one used to support the combustion of a rocket propellant

oxidizing agent -n

  1. a substance that oxidizes something esp. chemically (as by accepting electrons)

ox·i·do·re·duc·tase ['äk-sə-dō-ri-'dək-,tās, -,tāz] -n

  1. an enzyme that catalyzes an oxidation-reduction reaction

ox·ime ['äk-,sēm] -n

  1. any of various compounds containing the divalent group CNOH and obtained chiefly by the action of hydroxylamine on aldehydes and ketones

ox·im·e·ter [äk-'si-mə-tər] -n

  1. an instrument for measuring continuously the degree of oxygen saturation of the circulating blood

ox·lip ['äk-,slip] -n

  1. a Eurasian primula ( Primula elatior) having usu. yellow flowers

oxo ['äk-(,)sō] -adj

  1. containing oxygen

Oxon -abbr

  1. Oxford
  2. of Oxford
  3. Oxfordshire

Ox·o·ni·an [äk-'sō-nē-ən] -n, adj

  1. a student or graduate of Oxford University

ox·peck·er ['äks-,pe-kər] -n

  1. either of two small dull-colored African birds ( Buphagus erythrorhynchusand B. africanus) of the starling family that feed on ticks which they pick from the backs of infested cattle and wild mammals

ox·tail ['äks-,tāl] -n

  1. the tail of a beef animal
  2. the skinned tail used for food (as in soup)

ox·ter ['äk-stər] -n

  1. armpit
  2. arm

ox·tongue ['äks-,təŋ] -n

  1. a European hawkweed ( Picris echioides) that has yellow flowers and is now naturalized in the eastern U.S.

oxy ['äk-sē] -adj

  1. containing oxygen or additional oxygen often used in combination
    • oxy hemoglobin

oxy·acet·y·lene [,äk-sē-ə-'se-tə-lən, -,lēn] -adj

  1. of, relating to, or utilizing a mixture of oxygen and acetylene
    • an oxyacetylene torch

oxy·co·done [,äk-sē-'kō-,dōn] -n

  1. a narcotic analgesic C 18H 21NO 4used esp. in the form of its hydrochloride

ox·y·gen ['äk-si-jən] -n, adj

  1. a reactive element that is found in water, in most rocks and minerals, in numerous organic compounds, and as a colorless tasteless odorless diatomic gas constituting 21 percent of the atmosphere, that is capable of combining with all elements except the inert gases, that is active in physiological processes, and that is involved esp. in combustion
  2. something that sustains or fuels
    • disagreement is the true oxygen of these magazines -- Joseph Epstein

ox·y·gen·ate ['äk-si-jə-,nāt, äk-'si-jə-] -vt, n

  1. to impregnate, combine, or supply (as blood) with oxygen

oxygenate -n

  1. an oxygen-containing substance (as ethanol) used esp. in gasoline to promote more complete combustion

ox·y·gen·a·tor ['äk-si-jə-,nā-tər, äk-'si-jə-] -n

  1. one that oxygenates
  2. an apparatus that oxygenates the blood extracorporeally (as during open-heart surgery)

oxygen cycle -n

  1. the cycle whereby atmospheric oxygen is converted to carbon dioxide in animal respiration and regenerated by green plants in photosynthesis

oxygen debt -n

  1. a cumulative deficit of oxygen available for oxidative metabolism that develops during periods of intense bodily activity and must be made good when the body returns to rest

oxygen demand -n

  1. biochemical oxygen demand

ox·y·gen·ic [,äk-si-'je-nik] -adj

  1. of or relating to oxygen
  2. generating or producing oxygen
    • oxygenic photosynthesis

oxygen mask -n

  1. a device worn over the nose and mouth through which oxygen is supplied from a storage tank

oxygen tent -n

  1. a canopy which can be placed over a bedridden person and within which a flow of oxygen can be maintained

oxy·he·mo·glo·bin [,äk-si-'hē-mə-,glō-bən] -n

  1. hemoglobin loosely combined with oxygen that it releases to the tissues

oxy·hy·dro·gen [-'hī-drə-jən] -adj

  1. of, relating to, or utilizing a mixture of oxygen and hydrogen
    • an oxyhydrogen torch

ox·y·mo·ron [,äk-sē-'mȯr-,än] -n, adj, adv

  1. a combination of contradictory or incongruous words (as cruel kindness)
  2. something (as a concept) that is made up of contradictory or incongruous elements

oxy·phen·bu·ta·zone [,äk-sē-,fen-'byü-tə-,zōn] -n

  1. a phenylbutazone derivative C 19H 20N 2O 3having anti-inflammatory, analgesic, and antipyretic effects

oxy·phil·ic [,äk-si-'fi-lik] -adj

  1. acidophilic

oxy·tet·ra·cy·cline [-,te-trə-'sī-,klēn] -n

  1. a yellow crystalline broad-spectrum antibiotic C 22H 24N 2O 9produced by a soil actinomycete ( Streptomyces rimosus)

oxy·to·cic [,äk-si-'tō-sik] -adj, n

  1. hastening parturition
  2. inducing contraction of uterine smooth muscle

oxy·to·cin [-'tō-sᵊn] -n

  1. a pituitary octapeptide hormone C 43H 66N 12O 12S 2that stimulates esp. the contraction of uterine muscle and the secretion of milk

oxy·uri·a·sis [,äk-si-yu̇-'rī-ə-səs] -n

  1. infestation with or disease caused by pinworms (family Oxyuridae)