irregularity; non-standard; informal
Refers to something not following official rules, standards, or formal procedures. Often used in contexts like employment, transactions, or operations.
He obtained a visa through irregular procedures.
This company has many non-regular employees.
不規則 means 'irregular' in the sense of lacking a pattern or rhythm, not about rule-breaking.
Compound of 不 (fu, 'not') + 正規 (seiki, 'regular, formal, standard').