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¹irregular

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

: 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

Full Definition of IRREGULAR

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>

: 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>

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

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

— ir·reg·u·lar·ly adverb

See irregular defined for English-language learners

See irregular defined for kids

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

Related to IRREGULAR

Synonyms: aberrant, aberrational, abnormal, anomalous, atypical, deviate, devious, deviant, unnatural, untypical

Antonyms: natural, normal, regular, standard, typical

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>.

²irregular

noun

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

Full Definition of IRREGULAR

: 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

See irregular defined for English-language learners

First Known Use of IRREGULAR

15th century

IRREGULAR Defined for Kids

irregular

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

Definition of IRREGULAR for Kids

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

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

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

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

— ir·reg·u·lar·ly adverb

Medical Dictionary

irregular

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

Medical Definition of IRREGULAR

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

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

—ir·reg·u·lar·ly adverb