Cleaner to discourage bloke (9)
I believe the answer is:
detergent
'cleaner' is the definition.
(chemical that cleans)
'discourage bloke' is the wordplay.
'discourage' becomes 'deter' (synonyms).
'bloke' becomes 'gent' (both can mean a man).
'deter'+'gent'='DETERGENT'
'to' acts as a link.
(Other definitions for detergent that I've seen before include "Soluble cleansing agent" , "Soluble cleanser" , "help with the washing-up" , "Get tender (anag)" , "Cleansing solvent" .)