Ir -symbol

  1. iridium

IR -abbr

  1. information retrieval
  2. infrared
  3. inland revenue
  4. intelligence ratio
  5. internal revenue

IRA [,ī-(,)är-'ā; 'ī-rə] -n

  1. a retirement savings account in which income taxes on certain deposits and on all gains are deferred until withdrawals are made
  2. Irish Republican Army

Ira·ni·an [i-'rā-nē-ən, -'ra-, -'rä-; ī-'] -n, adj

  1. a native or inhabitant of Iran
  2. a branch of the Indo-European family of languages that includes Persian

iras·ci·ble [i-'ra-sə-bəl] -adj, n, adv

  1. marked by hot temper and easily provoked anger

irate [ī-'rāt, 'ī-,, i-'rāt] -adj, adv, n

  1. roused to ire
    • an irate taxpayer
  2. arising from anger
    • irate words

IRBM -abbr

  1. intermediate range ballistic missile

IRD -abbr

  1. integrated receiver decoder; integrated receiver descrambler

ire ['ī(-ə)r] -n, vt, adj

  1. intense and usu. openly displayed anger

Ire -abbr

  1. Ireland

ire·nic [ī-'re-nik, -'rē-] -adj, adv

  1. favoring, conducive to, or operating toward peace, moderation, or conciliation

irid -abbr

  1. iridescent

irid- -comb form

  1. rainbow
    • irid escent
  2. iris of the eye
    • irido logy

ir·i·des·cence [,ir-ə-'de-sᵊn(t)s] -n

  1. a lustrous rainbowlike play of color caused by differential refraction of light waves (as from an oil slick, soap bubble, or fish scales) that tends to change as the angle of view changes
  2. a lustrous or attractive quality or effect

ir·i·des·cent [-sᵊnt] -adj, adv

  1. having or exhibiting iridescence

irid·ic [i-'ri-dik, ī-'ri-dik] -adj

  1. of or relating to the iris of the eye

irid·i·um [i-'ri-dē-əm] -n

  1. a rare silver-white hard brittle very heavy metallic element

ir·i·dol·o·gy [,ī-rə-'dä-lə-jē] -n

  1. the study of the iris of the eye for indications of bodily health and disease

ir·id·os·mine [,ir-ə-'däz-,mēn] -n

  1. a mineral that is a native iridium osmium alloy usu. containing some rhodium and platinum

iris ['ī-rəs] -n

  1. rainbow
  2. the opaque contractile diaphragm perforated by the pupil and forming the colored portion of the eye
  3. iris diaphragm
  4. a similar device with a circular opening that can be varied in size
  5. any of a large genus ( Irisof the family Iridaceae, the iris family) of perennial herbaceous plants with linear usu. basal leaves and large showy flowers
  6. to make iridescent

Iris ['ī-rəs] -n

  1. the Greek goddess of the rainbow and a messenger of the gods

iris diaphragm -n

  1. an adjustable diaphragm of thin opaque plates that can be turned by a ring so as to change the diameter of a central opening usu. to regulate the aperture of a lens

Irish ['ī-rish] -n, adj

  1. natives or inhabitants of Ireland or their descendants esp. when of Celtic speech or culture
  2. the Celtic language of Ireland esp. as used since the later medieval period
  3. English spoken by the Irish
  4. irish whiskey

Irish bull -n

  1. an incongruous statement (as it was hereditary in his family to have no children)

Irish coffee -n

  1. hot sugared coffee and Irish whiskey topped with whipped cream

Irish confetti -n

  1. a rock or brick used as a missile

Irish Gaelic -n

  1. irish

Irish·ism ['ī-ri-,shi-zəm] -n

  1. a word, phrase, or expression characteristic of the Irish
  2. irish bull

Irish·ly ['ī-rish-lē] -adv

  1. in a manner characteristic of the Irish

Irish mail -n

  1. a 3- or 4-wheeled toy vehicle activated by a hand lever

Irish·man ['ī-rish-mən] -n

  1. a native or inhabitant of Ireland
  2. a person who is of Irish descent

Irish moss -n

  1. the dried and bleached plants of a red alga (esp. Chondrus crispus) used as an agent for thickening or emulsifying or as a demulcent and as a source of carrageenan
  2. a red alga that is a source of Irish moss called also carrageen

Irish·ness ['ī-rish-nəs] -n

  1. the fact or quality of being Irish

Irish potato -n

  1. potato

Irish·ry ['ī-rish-rē] -n

  1. irish
  2. Irish quality or character
  3. an Irish peculiarity or trait

Irish setter -n

  1. any of a breed of bird dogs resembling English setters but with a glossy mahogany-red coat

Irish stew -n

  1. a stew having as its principal ingredients meat (as lamb), potatoes, and onions in a thick gravy

Irish terrier -n

  1. any of a breed of active medium-sized terriers characterized by a dense close usu. reddish wiry coat

Irish water spaniel -n

  1. any of a breed of medium-sized retrievers characterized by a topknot, a heavy curly coat which is dark liver in color, and a short-haired tail

Irish whiskey -n

  1. whiskey made in Ireland chiefly of barley

Irish wolfhound -n

  1. any of a breed of very tall heavily built hounds having a rough wiry coat

Irish·wom·an ['ī-rish-,wu̇-mən] -n

  1. a woman born in Ireland or of Irish descent

iri·tis [ī-'rī-təs] -n

  1. inflammation of the iris of the eye

irk ['ərk] -vt

  1. to make weary, irritated, or bored
  2. the fact of being annoying
  3. a source of annoyance

irk·some ['ərk-səm] -adj, adv, n

  1. tending to irk : tedious
    • an irksome task

iro·ko [ə-'rō-(,)kō] -n

  1. a large tropical western African tree ( Chlorophora excelsa) of the mulberry family having strong streaky insect-resistant wood which is often used as a teak substitute
  2. this wood

iron ['ī(-ə)rn] -n

  1. a silver-white malleable ductile magnetic heavy metallic element that readily rusts in moist air, occurs native in meteorites and combined in most igneous rocks, is the most used of metals, and is vital to biological processes
  2. : something made of iron: as
  3. shackles for the hands or legs
  4. a heated metal implement used for branding or cauterizing
  5. a household device usu. with a flat metal base that is heated to smooth, finish, or press (as cloth)
  6. stirrup usu. used in pl.
  7. any of a series of numbered golf clubs having relatively thin metal heads
  8. great strength, hardness, or determination
  9. of, relating to, or made of iron
  10. resembling iron
  11. strong and healthy : robust
    • an iron constitution
  12. inflexible, unrelenting
    • iron determination
  13. holding or binding fast
    • an iron grip
  14. to furnish or cover with iron
  15. to shackle with irons
  16. to smooth with or as if with a heated iron
    • iron a shirt
  17. to remove (as wrinkles) by ironing
  18. to smooth or press cloth or clothing with a heated iron

Iron Age -n

  1. the period of human culture characterized by the smelting of iron and its use in industry beginning somewhat before 1000 b.c.in western Asia and Egypt

iron·bark ['ī(-ə)rn-,bärk] -n

  1. any of several Australian eucalypti having hard gray bark and heavy hard durable wood used esp. in heavy construction
  2. this wood

iron·bound [-'bau̇nd] -adj

  1. : bound with or as if with iron: as
  2. harsh, rugged
    • ironbound coast
  3. stern, rigorous
    • ironbound traditions

iron·clad [-'klad] -adj

  1. sheathed in iron armor used esp. of naval vessels
  2. : so firm or secure as to be unbreakable: as
  3. binding
    • an ironclad oath
  4. having no obvious weakness
    • an ironclad case against the defendant
  5. an armored naval vessel esp. of the mid to late 19th century

iron curtain -n

  1. an impenetrable barrier
    • the iron curtain between the ego and the unconscious -- C. J. Rolo
  2. a political, military, and ideological barrier that cuts off and isolates an area
  3. one formerly isolating an area under Soviet control

iron·er ['ī(-ə)r-nər] -n

  1. one that irons
  2. mangle

iron·fisted ['ī(-ə)rn-'fis-təd] -adj

  1. stingy, miserly
  2. being both harsh and ruthless
    • ironfisted methods

iron gray -n

  1. a slightly greenish dark gray

iron hand ['ī(-ə)rn-'han-dəd] -n, adj

  1. stern or rigorous control
    • ruled with an iron hand

iron·heart·ed ['ī(-ə)rn-'här-təd] -adj

  1. cruel, hard-hearted

iron horse -n

  1. locomotive
  2. a steam locomotive

iron·ic [,ī-'rä-nik also i-'rä-] -adj, n

  1. relating to, containing, or constituting irony
    • an ironic remark
    • an ironic coincidence
  2. given to irony
    • an ironic sense of humor

iron·i·cal·ly [-ni-k(ə-)lē] -adv

  1. in an ironic manner
  2. it is ironic, curious, or surprising

iron·ing ['ī(-ə)r-niŋ] -n

  1. the action or process of smoothing or pressing with or as if with a heated iron
  2. clothes ironed or to be ironed

ironing board -n

  1. a flat padded cloth-covered surface on which clothes are ironed

iro·nist ['ī-rə-nist] -n

  1. one who uses irony esp. in the development of a literary work or theme

iro·nize [-,nīz] -vb

  1. to make ironic in appearance or effect
  2. to use irony : speak or behave ironically

iron lung -n

  1. a device for artificial respiration in which rhythmic alternations in the air pressure in a chamber surrounding a patient's chest force air into and out of the lungs

iron maiden -n

  1. a supposed medieval torture device consisting of a hollow iron statue or coffin in the shape of a woman that is lined with spikes which impale the enclosed victim

iron man -n

  1. a man of unusual physical endurance

iron·mas·ter ['ī(-ə)rn-,mas-tər] -n

  1. a manufacturer of iron

iron·mon·ger [-,məŋ-gər, -,mäŋ-] -n

  1. a dealer in iron and hardware

iron·mon·gery [-g(ə-)rē] -n

  1. something made of metal
  2. hardware

iron out -vt

  1. to make smooth or flat by or as if by pressing
  2. to resolve or work out a solution to
    • ironed out their differences

iron oxide -n

  1. : any of several oxides of iron: as
  2. ferric oxide
  3. the monoxide FeO of iron

iron pyrites -n

  1. pyrite called also iron pyrite

iron ration -n

  1. an emergency ration

iron·side [-,sīd] -n

  1. a man of great strength or bravery

iron·stone ['ī(-ə)rn-,stōn] -n

  1. a hard sedimentary rock rich in iron
  2. a siderite in a coal region
  3. ironstone china

ironstone china -n

  1. a hard heavy durable white pottery developed in England early in the 19th century

iron sulfide -n

  1. any of several sulfides of iron

iron·ware ['ī(-ə)rn-,wer] -n

  1. articles made of iron

iron·weed [-,wēd] -n

  1. any of a genus ( Vernonia) of mostly weedy composite plants usu. having alternate leaves and perfect red, purple, or white tubular flowers in terminal cymose heads

iron·wood [-,wu̇d] -n

  1. any of numerous trees and shrubs (as a hornbeam or hop hornbeam) with exceptionally tough or hard wood
  2. the wood of an ironwood

iron·work [-,wərk] -n

  1. work in iron
  2. something made of iron
  3. a mill or building where iron or steel is smelted or heavy iron or steel products are made

iro·ny ['ī-rə-nē also 'ī(-ə)r-nē] -n

  1. a pretense of ignorance and of willingness to learn from another assumed in order to make the other's false conceptions conspicuous by adroit questioning called also Socratic irony
  2. the use of words to express something other than and esp. the opposite of the literal meaning
  3. a usu. humorous or sardonic literary style or form characterized by irony
  4. an ironic expression or utterance
  5. incongruity between the actual result of a sequence of events and the normal or expected result
  6. an event or result marked by such incongruity
  7. incongruity between a situation developed in a drama and the accompanying words or actions that is understood by the audience but not by the characters in the play called also dramatic irony tragic irony

Ir·o·quoi·an [,ir-ə-'kwȯi-ən] -n, adj

  1. a member of any of the peoples constituting the Iroquois
  2. an American Indian language family of eastern No. America including Cayuga, Cherokee, Mohawk, Onondaga, Oneida, Seneca, and Tuscarora

Ir·o·quois ['ir-ə-,kwȯi also -,kwä] -n

  1. an American Indian confederacy orig. of New York consisting of the Cayuga, Mohawk, Oneida, Onondaga, and Seneca and later including the Tuscarora
  2. a member of any of the Iroquois peoples

IRQ -abbr

  1. interrupt request

ir·ra·di·ance [i-'rā-dē-ən(t)s] -n

  1. radiance
  2. the density of radiation incident on a given surface usu. expressed in watts per square centimeter or square meter

ir·ra·di·ate [i-'rā-dē-,āt] -vb, adj, n

  1. to cast rays of light upon : illuminate
  2. to enlighten intellectually or spiritually
  3. to affect or treat by radiant energy (as heat)
  4. to treat by irradiation
  5. to emit like rays of light : radiate
    • irradiating strength and comfort
  6. to emit rays : shine

ir·ra·di·a·tion [i-,rā-dē-'ā-shən] -n

  1. exposure to radiation (as X rays or alpha particles)
  2. the application of radiation (as X rays or gamma rays) for therapeutic purposes or for sterilization (as of food)
  3. partial or complete sterilization by irradiation

ir·rad·i·ca·ble [i-'ra-di-kə-bəl, ,i(r)-] -adj, adv

  1. impossible to eradicate : deep-rooted
    • irradicable hatred

ir·ra·tio·nal [i-'ra-sh(ə-)nəl, ,i(r)-] -adj, n, adv

  1. : not rational: as
  2. not endowed with reason or understanding
  3. lacking usual or normal mental clarity or coherence
  4. not governed by or according to reason
    • irrational fears
  5. having a quantity other than that required by the meter
  6. containing such a syllable
  7. being an irrational number
    • an irrational root of an equation
  8. having a numerical value that is an irrational number
    • a length that is irrational

irrational -n

  1. an irrational being
  2. irrational number

ir·ra·tio·nal·ism [i-'ra-sh(ə-)nə-,li-zəm] -n, n or adj, adj

  1. a system emphasizing intuition, instinct, feeling, or faith rather than reason or holding that the universe is governed by irrational forces
  2. the quality or state of being irrational

irrational number -n

  1. a number that can be expressed as an infinite decimal with no set of consecutive digits repeating itself indefinitely and that cannot be expressed as the quotient of two integers

ir·re·al [i-'rē(-ə)l, ,i(r)-] -adj

  1. not real

ir·re·al·i·ty [,ir-ē-'a-lə-tē] -n

  1. unreality

ir·re·claim·able [,ir-i-'klā-mə-bəl] -adj, adv

  1. incapable of being reclaimed

ir·rec·on·cil·able [i-,re-kən-'sī-lə-bəl, -'re-kən-,, ,i(r)-] -adj, n, adv

  1. impossible to reconcile
    • irreconcilable differences

irreconcilable -n

  1. one that is irreconcilable
  2. a member of a group (as a political party) opposing compromise or collaboration

ir·re·cov·er·able [,ir-i-'kəv-rə-bəl, -'kə-və-] -adj, n, adv

  1. not capable of being recovered or rectified : irreparable
    • an irrecoverable loss

ir·re·cu·sa·ble [,ir-i-'kyü-zə-bəl] -adj, adv

  1. not subject to exception or rejection
    • irrecusable proof

irred -abbr

  1. irredeemable

ir·re·deem·able [,ir-i-'dē-mə-bəl] -adj, adv

  1. : not redeemable: as
  2. not terminable by payment of the principal
    • irredeemable bond
  3. inconvertible
  4. being beyond remedy : hopeless
    • irredeemable mistakes

ir·re·den·ta [,ir-i-'den-tə] -n

  1. a territory historically or ethnically related to one political unit but under the political control of another

ir·re·den·tism [-'den-,ti-zəm] -n, n or adj

  1. a political principle or policy directed toward the incorporation of irredentas within the boundaries of their historically or ethnically related political unit

ir·re·duc·ible [,ir-i-'dü-sə-bəl, -'dyü-] -adj, n, adv

  1. impossible to transform into or restore to a desired or simpler condition
    • an irreducible matrix
  2. incapable of being factored into polynomials of lower degree with coefficients in some given field (as the rational numbers) or integral domain (as the integers)
    • an irreducible equation
  3. impossible to make less or smaller
    • an irreducible minimum

ir·re·flex·ive [,ir-i-'flek-siv] -adj

  1. being a relation for which the reflexive property does not hold for any element of a given set

ir·re·form·able [,ir-i-'fȯr-mə-bəl] -adj, n

  1. incapable of being reformed : incorrigible
  2. not subject to revision or alteration
    • irreformable dogma

ir·re·fra·ga·ble [i-'re-frə-gə-bəl, ,i(r)-; ,ir-i-'fra-gə-] -adj, n, adv

  1. impossible to refute
    • irrefragable arguments
  2. impossible to break or alter
    • irrefragable rules

ir·re·fut·able [,ir-i-'fyü-tə-bəl; i-'re-fyə-tə-, ,i(r)-] -adj, n, adv

  1. impossible to refute : incontrovertible
    • irrefutable proof

irreg -abbr

  1. irregular

ir·re·gard·less [,ir-i-'gärd-ləs] -adv

  1. regardless

ir·reg·u·lar [i-'re-gyə-lər, ,i(r)-] -adj, adv

  1. not being or acting in accord with laws, rules, or established custom
    • irregular conduct
  2. not conforming to the usual pattern of inflection
    • irregular verbs
  3. strong
  4. not following a usual or prescribed procedure
  5. celebrated without either proclamation of the banns or publication of intention to marry
    • irregular marriage
  6. not belonging to or a part of a regular organized group
  7. not belonging to a regular army but raised for a special purpose
    • irregular troops
  8. lacking perfect symmetry or evenness
    • an irregular coastline
  9. having one or more floral parts of the same whorl different in size, shape, or arrangement
  10. zygomorphic
  11. lacking continuity or regularity esp. of occurrence or activity
    • irregular employment

irregular -n

  1. : one that is irregular: as
  2. a soldier who is not a member of a regular military force
  3. merchandise that has minor defects or that falls next below the manufacturer's standard for firsts

ir·reg·u·lar·i·ty [i-,re-gyə-'la-rə-tē, ,i(r)-] -n

  1. something that is irregular (as improper or dishonest conduct)
    • alleged irregularities in the city government
  2. the quality or state of being irregular
  3. constipation

ir·rel·a·tive [-'re-lə-tiv] -adj, adv

  1. : not relative:
  2. not related
  3. irrelevant

ir·rel·e·vance [-'re-lə-vən(t)s] -n

  1. the quality or state of being irrelevant
  2. something irrelevant

ir·rel·e·van·cy [-vən(t)-sē] -n

  1. irrelevance

ir·rel·e·vant [-vənt] -adj, adv

  1. not relevant : inapplicable
    • that statement is irrelevant to your argument

ir·re·li·gion [,ir-i-'li-jən] -n

  1. the quality or state of being irreligious

ir·re·li·gious [-'li-jəs] -adj, adv

  1. neglectful of religion : lacking religious emotions, doctrines, or practices
    • so irreligious that they exploit popular religion for professional purposes -- G. B. Shaw
  2. indicating lack of religion

ir·re·me·able [i-'rē-mē-ə-bəl, ,i(r)-] -adj

  1. offering no possibility of return
    • irremeable losses

ir·re·me·di·a·ble [,ir-i-'mē-dē-ə-bəl] -adj, n, adv

  1. not remediable
    • an irremediable error
  2. incurable

ir·re·mov·able [-'mü-və-bəl] -adj, n, adv

  1. not removable

ir·rep·a·ra·ble [i-'re-p(ə-)rə-bəl, ,i(r)- also ÷,ir-(r)ə-'per-ə-bəl] -adj, n, adv

  1. not reparable : irremediable
    • irreparable damage

ir·re·peal·able [,ir-i-'pē-lə-bəl] -adj, n

  1. not repealable

ir·re·place·able [-'plā-sə-bəl] -adj, n, adv

  1. not replaceable
    • an irreplaceable antique

ir·re·press·ible [-'pre-sə-bəl] -adj, n, adv

  1. impossible to repress, restrain, or control
    • irrepressible curiosity

ir·re·proach·able [-'prō-chə-bəl] -adj, n, adv

  1. not reproachable : blameless, impeccable
    • irreproachable conduct

ir·re·pro·duc·ible [i-,rē-prə-'dü-sə-bəl, ,i(r)-, -'dyü-] -adj, n

  1. not reproducible
    • irreproducible craftsmanship

ir·re·sist·ible [,ir-i-'zis-tə-bəl] -adj, n, adv

  1. impossible to resist
    • an irresistible attraction

ir·re·sol·u·ble [-'zäl-yə-bəl] -adj

  1. indissoluble
  2. having or admitting of no solution or explanation
    • an irresoluble question

ir·res·o·lute [i-'re-zə-,lüt, ,i(r)-, -lət] -adj, adv, n

  1. uncertain how to act or proceed : vacillating
    • irresolute legislators

ir·re·solv·able [,ir-i-'zäl-və-bəl, -'zȯl-] -adj

  1. incapable of being resolved
    • an irresolvable conflict
  2. not analyzable

ir·re·spec·tive of [,ir-i-'spek-tiv-] -prep

  1. regardless of
    • paid irrespective of how hard they work -- Lee Bowes

ir·re·spon·si·ble [,ir-i-'spän(t)-sə-bəl] -adj, n, adv

  1. : not responsible: as
  2. not answerable to higher authority
    • an irresponsible dictatorship
  3. said or done with no sense of responsibility
    • irresponsible accusations
  4. lacking a sense of responsibility
  5. unable esp. mentally or financially to bear responsibility

irresponsible -n

  1. a person who is irresponsible

ir·re·spon·sive [,ir-i-'spän(t)-siv] -adj, n

  1. not responsive
  2. not able, ready, or inclined to respond

ir·re·triev·able [,ir-i-'trē-və-bəl] -adj, n, adv

  1. not retrievable : impossible to regain or recover

ir·rev·er·ence [i-'rev-rənts, ,i(r)-, -'re-və-; -'re-vərn(t)s] -n

  1. lack of reverence
  2. an irreverent act or utterance

ir·rev·er·ent [-rənt; -vərnt] -adj, adv

  1. lacking proper respect or seriousness
  2. satiric

ir·re·vers·ible [,ir-i-'vər-sə-bəl] -adj, n, adv

  1. not reversible

ir·rev·o·ca·ble [i-'re-və-kə-bəl, ,i(r)- sometimes ,ir-(r)ə-'vō-kə-] -adj, n, adv

  1. not possible to revoke : unalterable
    • an irrevocable decision

irridenta [,ir-i-'den-tə] -n

(variant of irredenta)

  1. a territory historically or ethnically related to one political unit but under the political control of another

ir·ri·ga·ble ['ir-ə-gə-bəl] -adj

  1. suitable for irrigation
    • irrigable land

ir·ri·gate ['ir-ə-,gāt] -vb, n

  1. : wet, moisten: as
  2. to supply (as land or crops) with water by artificial means
  3. to flush (a body part) with a stream of liquid (as in removing a foreign body or medicating)
  4. to refresh as if by watering
  5. to practice irrigation

ir·ri·ga·tion [,ir-ə-'gā-shən] -n

  1. the therapeutic flushing of a body part with a stream of liquid
  2. the watering of land by artificial means to foster plant growth

ir·ri·ta·bil·i·ty [,ir-ə-tə-'bi-lə-tē] -n

  1. the property of protoplasm and of living organisms that permits them to react to stimuli
  2. : the quality or state of being irritable: as
  3. quick excitability to annoyance, impatience, or anger : petulance
  4. abnormal or excessive excitability of an organ or part of the body

ir·ri·ta·ble ['ir-ə-tə-bəl] -adj, n, adv

  1. : capable of being irritated: as
  2. easily exasperated or excited
    • gets irritable when he tires
  3. responsive to stimuli

irritable bowel syndrome -n

  1. a chronic functional disorder of the colon that is characterized esp. by constipation or diarrhea, cramping abdominal pain, and the passage of mucus in the stool abbr. IBS

ir·ri·tant ['ir-ə-tənt] -adj

  1. causing irritation
  2. tending to produce physical irritation

irritant -n

  1. something that irritates or excites

ir·ri·tate ['ir-ə-,tāt] -vb, adv

  1. to provoke impatience, anger, or displeasure in : annoy
  2. to induce irritability in or of
  3. to cause or induce displeasure or irritation

irritated -adj

  1. subjected to irritation
  2. roughened, reddened, or inflamed by an irritant
    • irritated eyes

ir·ri·ta·tion [,ir-ə-'tā-shən] -n

  1. the act of irritating
  2. something that irritates
  3. the state of being irritated
  4. a condition of irritability, soreness, roughness, or inflammation of a bodily part

ir·ri·ta·tive ['ir-ə-,tā-tiv] -adj

  1. serving to excite : irritating
  2. accompanied with or produced by irritation
    • irritative coughing

ir·ro·ta·tion·al [,ir-(r)ō-'tā-shnəl, -shə-nᵊl] -adj

  1. not rotating or involving rotation
  2. free of vortices
    • irrotational flow

ir·rupt [i-'rəpt] -vi, n

  1. to rush in forcibly or violently
  2. to undergo a sudden upsurge in numbers esp. when natural ecological balances and checks are disturbed
  3. erupt
    • the crowd irrupt ed in a fervor of patriotism -- Time

ir·rup·tive [-'rəp-tiv] -adj, adv

  1. irrupting or tending to irrupt
    • irruptive passions

IRS -abbr

  1. Internal Revenue Service