irregular

Contrary to rule, accepted order, or general practice.

Not conforming to legality, moral law, or social convention.

Not straight, uniform, or symmetrical.

Of uneven rate, occurrence, or duration.

Deviating from a type; atypical.

Having differing floral parts, as of a zygomorphic or asymmetric flower.

Falling below the manufacturer’s standard or usual specifications; imperfect.

Departing from the usual pattern of inflection, derivation, or word formation, as the present forms of the verb be or the plural noun children.

Not belonging to a permanent, organized military force.

One, such as an item of merchandise, that is irregular.