felonious

Felonious is an adjective used primarily in legal contexts to describe conduct that constitutes, or is characteristic of, a felony. A felony is a serious crime typically punishable by imprisonment for more than one year or by other severe penalties. In statutory and doctrinal language, "felonious" conveys the seriousness and criminal nature of the act.

Commonly accompanied by nouns such as assault, homicide, theft, or mobbing—e.g., felonious assault or felonious homicide—where the term emphasizes the nature of the offense as a felony rather than a lesser crime. The phrase "felonious intent" or "intent to commit a felonious act" refers to the mental element required to establish a felony in many jurisdictions; some places distinguish it from general criminal intent or malice.

Felonious is somewhat formal or archaic in everyday speech; in ordinary writing, "criminal" or specific felony names are often used instead. The word derives from felony, which comes from Old French felonie meaning crime or wicked act.