Not lawful; illegal.
The definition of nefarious is someone who is known for being very wicked.
The definition of criminal is someone or something related to the commission of a crime.
Evil or immoral:
Find another word for felonious. In this page you can discover 5 synonyms, antonyms, idiomatic expressions, and related words for felonious, like: unlawful, nefarious, criminal, illegal and wicked.