noun
lawbreaker; offender; violator
A person who breaks the law; a formal term used in legal or official contexts.
違法者は厳しく罰せられるべきだ。
Lawbreakers should be severely punished.
彼は交通違法者として逮捕された。
He was arrested as a traffic offender.
Compound of 違法 (illegal) + 者 (person). The exact historical derivation is uncertain, but the word follows a common pattern for forming agent nouns in Japanese.