The bar in Coronation Street, say? (4)
I believe the answer is:
soap
I believe this is a double definition.
'the bar' is the first definition.
(as in a bar of soap)
'coronation street say?' is the second definition.
(I know that Coronation Street is a soap)
'in' acts as a link.
(Other definitions for soap that I've seen before include "TV programme; cleanser" , "Coronation Street?" , "Cleaner - long-running TV show" , "A cleansing sort of TV serial" , "Washing substance" .)