1.NounA small nocturnal insect pest of humans, of species Cimex lectularius (common bedbug) and Cimex hemipterus (tropical bedbug) that feeds on the blood of humans during sleep.
"Fiona rapidly discovered that the hotel was infested with bedbugs."
2.NounAny similar insect of family Cimicidae, that feeds on the blood of humans and certain other warm-blooded animals.