Definition of irregular in English:

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Pronunciation: /əˈreɡyələr/


1Not even or balanced in shape or arrangement: her features were too irregular
More example sentences
  • This irregular arrangement of atoms not only defines a substance as glass, but also determines several of its properties.
  • Each panel features an elongated, irregular rectangle painted in acrylic in red, blue or black against a contrasting hue.
  • It is not that Thomas deliberately creates irregular shapes.
asymmetrical, nonuniform, uneven, crooked, misshapen, lopsided, twisted;
unusual, peculiar, strange, bizarre;
jagged, ragged, serrated, indented
lumpy, knobbly, gnarled
1.1Occurring at uneven or varying rates or intervals: an irregular heartbeat
More example sentences
  • Income can be withdrawn at irregular intervals to suit individual circumstances as long as the payments are in accordance with the above limits.
  • The rhythm is irregular, and the rate can vary or become sinus bradycardia because of the long pauses.
  • At the northwest corner, three to four people smoked at irregular intervals.
1.2 Botany (Of a flower) having the petals differing in size and shape; zygomorphic.
Example sentences
  • The only specimen of P. ramispina bears a few small, irregular branches, but is otherwise similar to E. siniansis; it does not merit a separate taxon.
  • The fasciated stem extended in one plane, and the phyllotaxy of floral primordia was irregular.
  • This is a list of species found on this site with irregular flowers.
2Contrary to the rules or to that which is normal or established: they were questioned about their involvement in irregular financial dealings
More example sentences
  • However, this was found in contradiction of OUSU rules, necessitating an irregular by-election to be held via an extraordinary meeting of the Postgraduate Assembly.
  • Indicated if labour is established but the contractions are of irregular intensity or duration.
  • The gentle formality of the house contrasts strongly with its irregular context and neighbouring suburban dwellings, but it does have precedents in New Zealand.
against the rules, out of order, improper, illegitimate, unscrupulous, unethical, unprofessional, unacceptable
informal shady
2.1 [attributive] (Of troops) not belonging to regular or established army units.
Example sentences
  • As the theatre of war moved south, so did the smallpox, primarily affecting civilians, camp followers, and irregular troops in both armies.
  • Not only did he understand the new tactics, he was also able to put them into practice using a smaller army made up of irregular troops.
  • In fact, regular as well as irregular troops opposed the US in many of the conflicts Boot cites.
2.2 Grammar (Of a verb or other word) having inflections that do not conform to the usual rules.
Example sentences
  • The questions required knowledge of some words, but also of an irregular verb form and some grammatical terminology.
  • In some irregular verbs, these functions are served by different forms.
  • Note that ‘to spy’ is always an irregular verb, only the third person form resembles the infinitive.


(usually irregulars)
1A member of an irregular military force.
Example sentences
  • The Filipino operational center of gravity was the ability to sustain its force of 100,000 irregulars in the field.
  • While repeating the Pentagon line that these irregulars were ‘forced to fight,’ Wallace acknowledged indirectly that the US military faces a hostile population.
  • Amitav Ghosh spent many weeks, at great personal risk, with the irregulars fighting the military regime in Burma.
2chiefly North American An imperfect piece of merchandise sold at a reduced price.


Late Middle English (in the sense 'not conforming to rule [especially that of the Church]'): via Old French from medieval Latin irregularis, from in- 'not' + regularis (see regular).

Words that rhyme with irregular


For editors and proofreaders

Syllabification: ir·reg·u·lar

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