Cleansing bar (4)
I believe the answer is:
soap
'cleansing bar' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for soap that I've seen before include "type of TV programme" , "Cleansing bar" , "Day-to-day TV series" , "Washing substance" , "Cleaning substance - melodramatic TV or radio series" .)