Bathroom fitting I’d bet needs throwing out (5)
I believe the answer is:
bidet
'bathroom fitting' is the definition.
(I've seen this before)
'i'd bet needs throwing out' is the wordplay.
'needs throwing out' indicates anagramming the letters.
'id'+'bet'='idbet'
'idbet' is an anagram of 'BIDET'.
(Other definitions for bidet that I've seen before include "where privates get soaked" , "Bathroom appliance" , "Where to wash" , "Bathroom fitting" , "Low basin for washing private parts" .)