Note: [See Illust. under {Aphrodite}.]
{Asclepias butterfly}. See under {Asclepias}.
{Butterfly fish} (Zo["o]l.), the ocellated blenny ({Blennius
ocellaris}) of Europe. See {Blenny}. The term is also
applied to the flying gurnard.
{Butterfly shell} (Zo["o]l.), 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.