Untidy, dancing in state of undress (6)
I believe the answer is:
nudity
'state of undress' is the definition.
(I've seen this before)
'untidy dancing' is the wordplay.
'dancing' is an anagram indicator.
'untidy' anagrammed gives 'NUDITY'.
'in' is the link.
(Other definitions for nudity that I've seen before include "feature of post-watershed TV?" , "Unclothed state" , "element of naturism" , "of discarded clothing" , "Moving at high speed" .)