Mature or mature to a point (5)
I believe the answer is:
ripen
'mature' is the definition.
(to ripen is to mature)
'mature to a point' is the wordplay.
'mature' becomes 'ripe' (similar in meaning).
'to a point' becomes 'n' (North).
'ripe'+'n'='RIPEN'
'or' acts as a link.
(Other definitions for ripen that I've seen before include "Grow to maturity like fruit" , "Become ready for eating" , "Develop fully" , "Come to fruition" , "Get ready for 2" .)