He didnt trust his wife to return a greeting (7)
I believe the answer is:
othello
'he didn't trust his wife' is the definition.
The definition suggests a singular noun which matches the answer.
'to return a greeting' is the wordplay.
'return' is a reversal indicator.
'a greeting' becomes 'hello' (hello is a kind of greeting).
'to' written backwards gives 'ot'.
'ot'+'hello'='OTHELLO'
Can you help me to learn more?
(Other definitions for othello that I've seen before include "Will's hero" , "Jealous character" , "Eponymous hero" , "Shakespearean hero" , "product of 12 [SHAKESPEARE] , inspiring 6 [VERDI]" .)