Gents confused getting nothing back in snuggling up (8)
I believe the answer is:
nestling
'snuggling up' is the definition.
'nestling' can be an answer for 'snuggling' ('nestle' can be a synonym of 'snuggle'). I am not sure about the 'up' bit.
'gents confused getting nothing back' is the wordplay.
'confused' indicates an anagram.
'getting' is an insertion indicator.
'nothing' becomes 'nil' (eg nil is zero in football).
'back' says the letters should be written backwards.
'nil' in reverse letter order is 'lin'.
'gents' anagrammed gives 'nestg'.
'nestg' enclosing 'lin' is 'NESTLING'.
'in' is the link.
Can you help me to learn more?
(Other definitions for nestling that I've seen before include "Chick" , "in a huddle" , "Young bird - snuggling" , "Settling in comfortably, against someone perhaps" , "Young bird not yet fledged" .)