Snug Lycra’s unattractive (4)
I believe the answer is:
ugly
'unattractive' is the definition.
('ugly' is associated in meaning with 'unattractive')
'snug lycra's' is the wordplay.
'UGLY' is hidden within the letters.
But, I'm not sure how this is indicated.
(Other definitions for ugly that I've seen before include "Repulsive in appearance" , "Unpleasing to the eye" , "offensive to look at" , "Lacking in beauty" , "Grotesque" .)