Best to clothe dancing nude looking firm (5,2)
I believe the answer is:
toned up
'looking firm' is the definition.
The answer and definition are not the same part of speech. However, adjectives and past participle verbs sometimes mean the same thing.
'best to clothe dancing nude' is the wordplay.
'best' becomes 'top' (top can mean the very best).
'to clothe' indicates putting letters inside.
'dancing' is an anagram indicator.
'nude' anagrammed gives 'nedu'.
'top' going around 'nedu' is 'TONED UP'.
Can you help me to learn more?
(Another definition for toned up that I've seen is " became healthier".)