irregular
adjective /ɪˈreɡjələ(r)/
  /ɪˈreɡjələr/
- not arranged in an even way; not having an even, smooth pattern or shape synonym uneven- irregular teeth
- an irregular outline
 Extra Examples- The cells are slightly irregular in shape.
- This stuff's great for renovating uneven, irregular surfaces.
 Oxford Collocations Dictionaryverbs- be
- become
 - highly
- very
- rather
- …
 
- not happening at times that are at an equal distance from each other; not happening regularly- A combination of irregular meals and insufficient sleep was to blame.
- an irregular heartbeat
- irregular attendance at school
- He visited his parents at irregular intervals.
 Oxford Collocations Dictionaryverbs- be
- become
 - highly
- very
- rather
- …
 
- not normal; not according to the usual rules synonym abnormal- some somewhat irregular business practices
- His behaviour is highly irregular.
 Oxford Collocations Dictionaryverbs- be
- seem
 - highly
- most
- very
- …
 
- (grammar) not formed in the normal way- an irregular verb
 
- (of a soldier, etc.) not part of a country’s official army opposite regular
Word Originlate Middle English (in the sense ‘not conforming to rule (especially that of the Church)’): via Old French from medieval Latin irregularis, from in- ‘not’ + regularis (from regula ‘rule’).