Aglais io, a red butterfly with distinctive large eyespots, of the family Nymphalidae.

A folding pocket knife with two handles counter-rotating around the tang such that, when closed, the blade is concealed within grooves in the handles.

A ray (fish) of the family Gymnuridae (or, in some systems, the subfamily Gymnurinae).

plural of butterfly ray

A swimming stroke in which the body is prone, the arms are moved in simultaneous circles, and the feet are kicked up and down.

plural of butterfly knife

plural of butterfly effect

A small pelagic sea snail of the suborder Thecosomata.

A type of bend knot, very similar to the butterfly knot, but used to join two ropes.

plural of butterfly knot