Burlesque outfit with small opening (4)
I believe the answer is:
skit
'burlesque' is the definition.
(I've seen this before)
'outfit with small opening' is the wordplay.
'outfit' becomes 'kit' (kitting is a kind of outfiting**).
'with' is a charade indicator (letters next to each other).
'opening' indicates taking the first letters.
The initial letter of 'small' is 's'.
'kit' after 's' is 'SKIT'.
(Other definitions for skit that I've seen before include "Funny scene" , "Short play which makes fun of something" , "Send-up" , "Parodic sketch" , "Comedy item" .)