Newly-wed rightly in prison (9)
I believe the answer is:
bridewell
'prison' is the definition.
(I've seen this before)
'newly-wed rightly' is the wordplay.
'newly wed' becomes 'bride' (I've seen this in other clues).
'rightly' becomes 'well' (I've seen this before).
'bride'+'well'='BRIDEWELL'
'in' acts as a link.
(Other definitions for bridewell that I've seen before include "gaol" , "Former prison" , "stir once" , "old prison" , "Can, perhaps" .)