Undefeated Laila (3)
I believe the answer is:
ali
'undefeated laila' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for ali that I've seen before include "Muhammad ..., former boxer" , "Muhammad - - , legendary boxer" , "Muhammad's son-in-law" , "Muhammad ..., famous boxer" , "Lepidopterous floater, apian stinger, d. 2016" .)