| noun | a member of an irregular armed force that fights a stronger force by sabotage and harassment |
| noun | merchandise that has imperfections; usually sold at a reduced price without the brand name |
| adjective | contrary to rule or accepted order or general practice “irregular hiring practices” |
| adjective | not occurring at expected times |
| adjective | (used of the military) not belonging to or engaged in by regular army forces “irregular troops” |
| adjective | (of solids) not having clear dimensions that can be measured; volume must be determined with the principle of liquid displacement |
| adjective | falling below the manufacturer's standard “irregular jeans” |
| adjective | deviating from normal expectations; somewhat odd, strange, or abnormal “these days large families are atypical” |
| adjective | lacking continuity or regularity “an irregular worker” |
| adjective | (of a surface or shape); not level or flat or symmetrical “walking was difficult on the irregular cobblestoned surface” |
| adjective | independent in behavior or thought “she led a somewhat irregular private life” |
| irregularity | noun | not characterized by a fixed principle or rate; at irregular intervals |
| atypicality | noun | any state that is not typical |
| temporariness | noun | the property of lasting only a short time |
| maverick | noun | someone who exhibits great independence in thought and action |