Drink gallons with no toilet around (6)
I believe the answer is:
oolong
'drink' is the definition.
(I know that oolong is a type of tea)
'gallons with no toilet around' is the wordplay.
'gallons' becomes 'G' (abbreviation).
'with' is a charade indicator (letters next to each other).
'toilet' becomes 'loo' (loo can informally mean a toilet).
'around' says the letters should be written in reverse.
'g'+'no'+'loo'='gnoloo'
'gnoloo' written backwards gives 'OOLONG'.
(Other definitions for oolong that I've seen before include "oriental tea" , "Kind of Chinese tea" , "A variety of black China tea with green tea flavour" , "sort of leaves" , "Kind of China tea" .)