Workout wear (6)
(Other definitions for tee that I've seen before include "Golfer drives from it" , "Golf starting point" , "Golfing item" , "Golfer's support" , "Drive off it, half-tittering" .)
'workout wear' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for sweats that I've seen before include "Clothes" , "Perspires" , "old soldiers" , "Works hard" , "Casual dress" .)