Wash could be on pegs (6)
I believe the answer is:
sponge
'wash' is the definition.
(thesaurus)
'could be on pegs' is the wordplay.
'could be' indicates an anagram.
'on'+'pegs'='onpegs'
'onpegs' with letters rearranged gives 'SPONGE'.
(Other definitions for sponge that I've seen before include "Light cake; sea creature" , "Aquatic creature - cadge" , "Soft aquatic creature" , "Piece of porous rubber" , "Aquatic invertebrate with a soft porous body" .)