A fat insect? (9)
I believe the answer is:
butterfly
'a fat insect?' is the definition.
'butterfly' can be an answer for 'insect?' (butterflies are insects). I'm not sure about the 'a fat' bit.
'a fat insect?' is the wordplay.
'a fat' becomes 'butter' (I've seen this before).
'insect?' becomes 'fly' (fly is a kind of insect).
'butter'+'fly'='BUTTERFLY'
Can you help me to learn more?
(Other definitions for butterfly that I've seen before include "Peacock or red admiral, for example" , "Lepidopterous insect" , "Skipper for instance" , "Insect with four coloured wings and feelers" , "Insect with large, usually brightly coloured, wings" .)