Wipe rear end in comfort (5)
I believe the answer is:
erase
'wipe' is the definition.
(I've seen this in another clue)
'rear end in comfort' is the wordplay.
'end' says to take the final letters.
'in' is an insertion indicator.
'comfort' becomes 'ease' (synonyms).
The final letter of 'rear' is 'r'.
'r' placed within 'ease' is 'ERASE'.
(Other definitions for erase that I've seen before include "Eliminate" , "Remove all traces of" , "Clear" , "Eradicate" , "Destroy recording on audio or video tape" .)