Workout garments - father wearing set wasn't relaxed (10)
I believe the answer is:
sweatpants
'workout garments' is the definition.
I don't know anything about this answer so I can't tell whether this works.
'father wearing set wasn't relaxed' is the wordplay.
'father' becomes 'pa' (pa is a kind of father).
'wearing' indicates putting letters inside.
'relaxed' is an anagram indicator.
'set'+'wasnt'='setwasnt'
'setwasnt' with letters rearranged gives 'sweatnts'.
'pa' put inside 'sweatnts' is 'SWEATPANTS'.
Can you help me to learn more?
(Other definitions for sweatpants that I've seen before include "clothing" , "Loose, warm garment - wasn't a pest (anag)" , "Sports bags" , "Joggers" .)