Fluttering insect — mum shows no sign of hesitation (4)
I believe the answer is:
moth
'fluttering insect' is the definition.
'moth' can be an answer for 'insect' (moth is a kind of insect). I am unsure of the 'fluttering' bit.
'mum shows no sign of hesitation' is the wordplay.
'mum' becomes 'mother' (I've seen this before).
'shows no' suggests deleting specific letters.
'sign of hesitation' becomes 'er'.
'mother' with 'er' removed is 'MOTH'.
Can you help me to learn more?
(Other definitions for moth that I've seen before include "Nocturnal winged insect" , "night flyer" , "Night-flier" , "Cloth-eating insect" , "Night flying insect" .)