Use sponge, perhaps, to hold water (4)
I believe the answer is:
wash
This clue could be a double definition.
'use sponge' is the first definition.
'wash' can be an answer for 'sponge' (thesaurus). I'm not sure about the 'use' bit.
'to hold water' is the second definition.
(thesaurus)
'perhaps' is the link.
Can you help me to learn more?
(Other definitions for wash that I've seen before include "Laundry" , "Clean; dilute coat" , "Clean with soap" , "Cancelled event - utter failure" , "Rough water left by a moving boat" .)