Mewl (7)
I believe the answer is:
whimper
'mewl' is the definition.
(I know that mewl can be written as whimper)
This is the entire clue.
(Other definitions for whimper that I've seen before include "Snivel" , "Whine" , "Sob" , "Cry feebly or plaintively" , "Cry weakly or softly" .)