Singular niff? English drunkard (6)
I believe the answer is:
sponge
'drunkard' is the definition.
(I've seen this before)
'singular niff? english' is the wordplay.
'singular' becomes 's' (abbreviation sometimes used in dictionaries).
'niff?' becomes 'pong' (I've seen this before).
'english' becomes 'e' (abbreviation).
's'+'pong'+'e'='SPONGE'
(Other definitions for sponge that I've seen before include "Marine animal often found in bathroom" , "clean with damp cloth" , "Sea creature often found in bathroom" , "Sea animal often found in bath" , "Marine animal with ability as at 3 Down" .)