/ ɪˌregjəˈlærəti; NAmE / noun ( pl. -ies )
1.
[ C , U ] an activity or a practice which is not according to the usual rules, or not normal :
alleged irregularities in the election campaign
suspicion of financial irregularity
2.
[ C , U ] something that does not happen at regular intervals :
a slight irregularity in his heartbeat
3.
[ U , C ] something that is not smooth or regular in shape or arrangement :
The paint will cover any irregularity in the surface of the walls.
—compare regularity
••
WORD ORIGIN
Middle English : from Old French irregularite , from late Latin irregularitas , from irregularis , from in- not + regularis (from regula rule).