Bath bubbles (4)
I believe the answer is:
suds
'bath bubbles' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for suds that I've seen before include "Mass of soap bubbles" , "Lathery bubbles" , "Soapy water" , "Soapy froth" , "Froth of soap and water" .)