Forbid these to stop partners wishing to make contract (5)
I believe the answer is:
banns
'stop partners wishing to make contract' is the definition.
I can't tell whether this defines the answer.
'forbid these' is the wordplay.
'forbid' becomes 'ban' (banning is a kind of forbiding).
'these' becomes 'ns' (I can't justify this - if you can you should believe this answer much more).
'ban'+'ns'='BANNS'
'to' acts as a link.
Can you help me to learn more?
(Other definitions for banns that I've seen before include "Notices of marriage" , "Notice of a wedding" , "Pre-wedding notice" , "Notice of marriage read in church" , "Proclamation of intended marriage" .)