Expression of affection (10)
I believe the answer is:
endearment
'expression of affection' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for endearment that I've seen before include "Fondness" , "Affectionate word" , "Word of affection" , "Affectionate term" , "Affectionate utterance" .)