Comedian's back, one with incisive material (7)
I believe the answer is:
nankeen
'material' is the definition.
(nankeen is a kind of material)
'comedian's back one with incisive' is the wordplay.
'back' says to take the final letters.
'one' becomes 'an' ('a' and 'an' can mean 'one').
'with' means one lot of letters go next to another.
'incisive' becomes 'keen' (synonyms).
The last letter of 'comedian' is 'n'.
'n'+'an'+'keen'='NANKEEN'
(Other definitions for nankeen that I've seen before include "Durable yellow cotton fabric, originally from China" , "Buff colour" , "mustard colour" , "Hard-wearing fabric, originally from China" , "Yellowish stuff" .)