Ill-tempered or annoyed - with a garment? (6)
I believe the answer is:
shirty
'ill-tempered or annoyed with a garment?' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for shirty that I've seen before include "Bad-tempered (like a garment?)" , "Irritable" , "Tetchy" , "Ill-tempered (informal)" , "Ill-tempered or annoyed with a garment" .)