demon
n
1 an evil spirit or devil
2 a person, habit, obsession, etc., thought of as evil, cruel, or persistently tormenting
3 (Also called)
daemon, daimon an attendant or ministering spirit; genius
the demon of inspiration
a a person who is extremely skilful in, energetic at, or devoted to a given activity, esp. a sport
a demon at cycling
b (as modifier)
a demon cyclist
5 a variant spelling of →
daemon →
1
6 (Austral. and N.Z.)
informal, archaic a detective or policeman
(C15: from Latin daemon evil spirit, spirit, from Greek daimon spirit, deity, fate; see daemon)