Call after a denim ensemble that's no longer used by spouse (6,4)
I believe the answer is:
maiden name
'no longer used by spouse' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'call after a denim ensemble' is the wordplay.
'call' becomes 'name' (as in calling or naming someone something).
'after' means one lot of letters go next to another.
'ensemble' indicates anagramming the letters.
'a'+'denim'='adenim'
'adenim' with letters rearranged gives 'maiden'.
'name' put after 'maiden' is 'MAIDEN NAME'.
'that's' acts as a link.
Can you help me to learn more?
(Another definition for maiden name that I've seen is " former title".)