unregular
/ˌʌnrɪˈɡjʊlər, ˌʌnriˈɡjʊlər/Definitions
1. adjective
not regular in form, arrangement, or occurrence
“The unregular bus schedule made it difficult for commuters to plan their day.”
2. adverb
in an irregular manner or at irregular intervals
“The unregular beat of the drum created a unique rhythm.”
3. noun
something that is irregular in form or arrangement
“The unregular shapes of the sculptures made them visually interesting.”