irrégulier

Irrégulier is a French adjective meaning not regular or not conforming to a pattern. It describes things that lack regularity, predictability, or standard form, and it is used across everyday language as well as technical contexts. The term can refer to schedules or rhythms that do not follow a steady pattern, to shapes or processes that are uneven or inconsistent, or to phenomena that deviate from expected norms.

Etymology: irrégulier comes from Latin irregularis, with the French prefix in- meaning not and the stem regularis. The form reflects typical negation in French adjectives, with agreement in gender and number.

Grammar: the adjective agrees with the noun in gender and number: masculin singulier irrégulier, féminin singulier irrégulière, pluriel irréguliers, irrégulières. It is commonly used with nouns such as horaire irrégulier, rythme irrégulier, paiement irrégulier, oré pronounced variable in various contexts. The related noun is irrégularité, denoting irregularity.

Usage notes: irrégulier can carry a neutral descriptive tone or a critical nuance depending on context. It often contrasts with régulier, normal, or constant. In linguistics, it is well established in the term verbe irrégulier to describe verbs whose conjugation deviates from standard patterns.

See also: irregularity; irregular verb (verbe irrégulier); irregular shapes or rhythms in science, music, and design.