Nana married to leave service (3)
I believe the answer is:
ass
'nana' is the definition.
Both the answer and definition are singular nouns.
Maybe they are linked in a way I don't understand?
'married to leave service' is the wordplay.
'married' becomes 'm' (abbreviation, e.g. in genealogy).
'to leave' indicates named letters should be taken away.
'service' becomes 'mass' (religious service).
'mass' with 'm' taken out is 'ASS'.
Can you help me to learn more?
(Other definitions for ass that I've seen before include "'The law is a - - - a idiot' (Mr Bumble)" , "Braying creature" , "Buffoon" , "Donkey - one that's foolish" , "Clinton's behind" .)