Dainty foxtrot involved in line dancing (5)
I believe the answer is:
elfin
'dainty' is the definition.
(thesaurus)
'foxtrot involved in line dancing' is the wordplay.
'foxtrot' becomes 'f' (phonetic alphabet: alpha, bravo, charlie etc.).
'involved in' means one lot of letters goes inside another.
'dancing' indicates an anagram.
'line' with letters rearranged gives 'elin'.
'f' inserted inside 'elin' is 'ELFIN'.
(Other definitions for elfin that I've seen before include "Small; impish" , "puckish" , "Mischievous sprite" , "Small, mischievous and charming" , "Delicate, slight" .)