A service not returned (3)
I believe the answer is:
ace
This clue might be a double definition.
'a service' is the first definition.
(ace is a kind of service)
'not returned' is the second definition.
The answer and definition are different parts of speech. However, past participle verbs and adjectives can occasionally mean the same thing.
Can you help me to learn more?
(Other definitions for ace that I've seen before include "hotshot" , "One in playing-cards" , "Service that's never returned" , "Hole in one; very good" , "Playing card with single spot" .)