Butterfly

n. pl. Butterflies ().

1. A general name for the numerous species of diurnal Lepidoptera.
   
Asclepias butterfly .
See under Asclepias.
Butterfly fish (Zoöl.),
the ocellated blenny (Blennius ocellaris) of Europe. See Blenny. The term is also applied to the flying gurnard.
Butterfly shell (Zoöl.),
a shell of the genus Voluta.
Butterfly valve (Mech.),
a kind of double clack valve, consisting of two semicircular clappers or wings hinged to a cross rib in the pump bucket. When open it somewhat resembles a butterfly in shape.