Get weary after a short time in formal clothes (6)
I believe the answer is:
attire
'formal clothes' is the definition.
(I've seen this before)
'get weary after a short time' is the wordplay.
'get weary' becomes 'tire' (I've seen this before).
'after' says to put letters next to each other.
'short time' becomes 't' (abbreviation for time).
'a'+'t'='at'
'tire' put after 'at' is 'ATTIRE'.
'in' is the link.
(Other definitions for attire that I've seen before include "12" , "Habit" , "Formal dress or costume" , "I treat badly the dress." , "(To) dress; fine clothes" .)