Butterfly mark (5)
I believe the answer is:
comma
I believe this clue is a double definition.
'butterfly' is the first definition.
(comma is a kind of butterfly)
'mark' is the second definition.
(comma is a kind of mark)
(Other definitions for comma that I've seen before include "Punctuation mark indicating slight pause" , "Brief stop" , "breathtaking marking?" , "Puncuation mark" , "Kind of butterfly" .)