Pants perhaps turned German off (12)
I believe the answer is:
undergarment
'pants perhaps' is the definition.
(pants is a kind of undergarment)
'turned german off' is the wordplay.
'off' indicates anagramming the letters.
'turned'+'german'='turnedgerman'
'turnedgerman' anagrammed gives 'UNDERGARMENT'.
(Other definitions for undergarment that I've seen before include "Eg, vest or pants" , "Item of clothing worn next to the skin" , "drawers, maybe" , "Pants perhaps" .)