Clean water in sealed container (5)
I believe the answer is:
rinse
'clean' is the definition.
(thesaurus)
'water in sealed container' is the wordplay.
'container' says the answer is hidden in the clue.
'RINSE' is hidden within 'water in sealed'.
(Other definitions for rinse that I've seen before include "Run water through" , "blue one on top?" , "Wash - siren (anag)" , "Colour" , "Wash without using soap" .)