FELO'NIOUS, adjective 1. Malignant; malicious; indicating or proceeding from a depraved heart or evil purpose; villainous; traitorous; perfidious; as a felonious deed. 2. In law, proceeding from an evil heart or purpose; done with the deliberate purpose to commit a crime; as felonious homicide.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI