Dairy topping rotting in tip (4)
I believe the answer is:
doff
'tip' is the definition.
(I've seen this in another clue)
'dairy topping rotting' is the wordplay.
'dairy' becomes 'd' (this might be a standard abbreviation which I don't know about).
'topping' is a charade indicator (letters next to each other).
'rotting' becomes 'off' (something going off is rotting).
'd'+'off'='DOFF'
'in' is the link.
Can you help me to learn more?
(Other definitions for doff that I've seen before include "Remove, hat say" , "Take off (clothing) - remove (hat)" , "Remove one's cap" , "shed" , "Remove (e.g. hat)" .)