Brit's restroom (3)
I believe the answer is:
loo
'brit's restroom' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for loo that I've seen before include "Rest room" , "A colloquial toilet" , "Toilet (informal)" , "Card game; the 'smallest room'" , "Privy" .)