IRREGULAR
—adjective. 1 not regular; unsymmetrical, uneven; varying in form. 2 not occurring at regular intervals. 3 contrary to a rule, principle, or custom; abnormal. 4 (of troops) not belonging to the regular army. 5 (of a verb, noun, etc.) Not inflected according to the usual rules. 6 disorderly. —none. (in plural.) Irregular troops. ? irregularity none. (plural. -ies). Irregularly adv.