Lie next to some comma butterflies (4)
I believe the answer is:
abut
'lie next to' is the definition.
(I've seen this before)
'some comma butterflies' is the wordplay.
'some' says the answer is hidden in the clue (some parts of the word are used).
'ABUT' is hidden within 'comma butterflies'.
(Other definitions for abut that I've seen before include "Be next to -- share a boundary" , "Adjoin, be contiguous to" , "Adjoin -- 19 (rev)" , "End or lean against, say a building" , "Lie next to" .)