irregular

Borrowed from Old French irreguler, from Medieval Latin or Late Latin irrēgulāris, from in- + regularis, equivalent to ir- +‎ regular.

• (US) IPA^(key): /ɪˈɹɛɡjəlɚ/

irregular (comparative more irregular, superlative most irregular)

1. nonstandard; not conforming to rules or expectations
   • 1967, Sleigh, Barbara, Jessamy, 1993 edition, Sevenoaks, Kent: Bloomsbury, →ISBN, page 33:

     ‘ “It would be most irregular Grandpa!” says Miss Cecily frowning and tapping her foot. “Well, we’re a pretty irregular family so that’s neither here nor there,” says the old man, impish like. [...] ’

2. (of a surface) rough
3. without symmetry, regularity, or uniformity
   • 1944, Miles Burton, chapter 5, in The Three Corpse Trick:

     The hovel stood in the centre of what had once been a vegetable garden, but was now a patch of rank weeds. Surrounding this, almost like a zareba, was an irregular ring of gorse and brambles, an unclaimed vestige of the original common.

   • 2013 January 1, Paul Bartel, Ashli Moore, “Avian Migration: The Ultimate Red-Eye Flight”, in American Scientist, volume 101, number 1, page 47–48:

     Many of these classic methods are still used, with some modern improvements. For example, with the aid of special microphones and automated sound detection software, ornithologists recently reported […] that pine siskins (Spinus pinus) undergo an irregular, nomadic type of nocturnal migration.

   • 2013 July 19, Ian Sample, “Irregular bedtimes may affect children's brains”, in The Guardian Weekly, volume 189, number 6, page 34:

     Irregular bedtimes may disrupt healthy brain development in young children, according to a study of intelligence and sleeping habits.  ¶ Going to bed at a different time each night affected girls more than boys, but both fared worse on mental tasks than children who had a set bedtime, researchers found.

4. (geometry, of a polygon) not regular; having sides that are not equal or angles that are not equal
5. (geometry, of a polyhedron) whose faces are not all regular polygons (or are not equally inclined to each other)
6. (grammar, of a word) not following the regular or expected patterns of inflection in a given language

   "Calves", "cacti", and "children" are irregular plurals.

   I hate learning all the irregular conjugations in French.

• regular

• irregular plural
• irregular verb

irregular (plural irregulars)

1. a soldier who is not a member of an official military force and, often, does not follow regular army tactics
2. one who does not regularly attend a venue
   • 2015, Brian Cook, Hands Across The Sea (page 190)

     There's one neighborhood tavern where the regulars and irregulars go after a hard day to unlax and rewind, throw back a few, and just hang out - you know the one.

Borrowed from Late Latin irrēgulāris.

• (Balearic, Central) IPA^(key): /i.rə.ɡuˈla/
• (Valencian) IPA^(key): /i.re.ɡuˈlaɾ/

irregular (masculine and feminine plural irregulars)

1. irregular

   Antonym: regular

• irregularitat

Borrowed from Late Latin irrēgulāris.

irregular m or f (plural irregulares)

1. irregular

Borrowed from Late Latin irrēgulāris.

irregular m or f (plural irregulares, comparable)

1. irregular; nonstandard
2. (grammar) irregular (not following an inflectional paradigm)

• regular

Borrowed from Late Latin irrēgulāris.

• IPA^(key): /ireɡuˈlaɾ/, [ireɣuˈlaɾ]

irregular (plural irregulares)

1. irregular

   Antonym: regular