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adjective ir·reg·u·lar \i-ˈre-gyə-lər, ˌi(r)-\

Simple Definition of irregular

  • : not normal or usual : not following the usual rules about what should be done

  • : not even or smooth : not regular in form or shape

  • : happening or done at different times that change often

Source: Merriam-Webster's Learner's Dictionary

Full Definition of irregular

  1. 1 a :  not being or acting in accord with laws, rules, or established custom <irregular conduct> b :  not conforming to the usual pattern of inflection <irregular verbs>; specifically :  strong 16 c :  not following a usual or prescribed procedure; especially British :  celebrated without either proclamation of the banns or publication of intention to marry <irregular marriage>

  2. 2 :  not belonging to or a part of a regular organized group; specifically :  not belonging to a regular army but raised for a special purpose <irregular troops>

  3. 3 a :  lacking perfect symmetry or evenness <an irregular coastline> b :  having one or more floral parts of the same whorl different in size, shape, or arrangement; specifically :  zygomorphic

  4. 4 :  lacking continuity or regularity especially of occurrence or activity <irregular employment>

irregularly adverb

Examples of irregular in a sentence

  1. His behavior as a teacher was highly irregular.

  2. Her application was handled in an irregular manner.

  3. a very jagged, irregular surface

  4. The stone has an irregular shape.

  5. He has a very irregular schedule.

  6. The festival has been held at irregular intervals.

Origin of irregular

Middle English irreguler, from Anglo-French, from Late Latin irregularis not in accordance with rule, from Latin in- + regularis regular

First Known Use: 14th century

Synonym Discussion of irregular

irregular, anomalous, unnatural mean not conforming to rule, law, or custom. irregular implies not conforming to a law or regulation imposed for the sake of uniformity in method, practice, or conduct <concerned about his irregular behavior>. anomalous implies not conforming to what might be expected because of the class or type to which it belongs or the laws that govern its existence <her drive made her an anomalous figure in a sleepy organization>. unnatural suggests what is contrary to nature or to principles or standards felt to be essential to the well-being of civilized society <prisoners treated with unnatural cruelty>.



noun ir·reg·u·lar

Simple Definition of irregular

  • : a soldier who does not belong to a country's official army

Source: Merriam-Webster's Learner's Dictionary

Full Definition of irregular

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

15th Century

First Known Use of irregular

15th century

IRREGULAR Defined for Kids


adjective ir·reg·u·lar \i-ˈreg-yə-lər\

Definition of irregular for Students

  1. 1 :  not following custom or rule <Her methods are most irregular.>

  2. 2 :  not following the usual manner of inflection <The verb “sell” is irregular because its past tense is “sold,” not “selled.”>

  3. 3 :  not straight, smooth, or even <an irregular coastline>

  4. 4 :  not continuous or coming at set times <He works irregular hours.>

irregularly adverb

Medical Dictionary


adjective ir·reg·u·lar \(ˈ)ir-ˈ(r)eg-yə-lər\

Medical Definition of irregular

  1. 1:  lacking perfect symmetry of form :  not straight, smooth, even, or regular <irregular teeth>

  2. 2a:  lacking continuity or regularity of occurrence, activity, or function <irregular breathing>bof a physiological function :  failing to occur at regular or normal intervals <irregular menstruation> <have your bowels been irregular>cof an individual :  failing to defecate at regular or normal intervals <was constipated and very irregular>

irregularly adverb

Law Dictionary


adjective ir·reg·u·lar \ir-ˈre-gyə-lər\

Legal Definition of irregular

  1. :  not in accord with laws, rules, procedures, or established custom

irregularly adverb

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