Dancing nude almost felt necessary (7)
I believe the answer is:
needful
'necessary' is the definition.
('needful' can be similar in meaning to 'necessary')
'dancing nude almost felt' is the wordplay.
'dancing' indicates anagramming the letters.
'almost' means to remove the last letter (most of the word but not all of it).
'felt' with its final letter taken off is 'fel'.
'nude'+'fel'='nudefel'
'nudefel' is an anagram of 'NEEDFUL'.
(Other definitions for needful that I've seen before include "Necessary for nude elf" , "Indispensable" , "poor" , "Nude elf (anag.)" , "Poverty-stricken" .)