irregular
Definition of irregular:
part of speech: noun
A soldier not in regular service; one not following any fixed rule; in bot, a flower in which the parts of any of the verticils differ in size.
part of speech: adjective
Not according to usual forms or rules; not according to established principles or customs; not in conformity to law; wanting symmetry; not regular, as regards mode of life; vicious.
part of speech: noun
Irregularity.