Points introduced in characteristic passage (7)
I believe the answer is:
transit
'passage' is the definition.
('transit' can be a synonym of 'passage')
'points introduced in characteristic' is the wordplay.
'points' becomes 'ns' (N is an example).
'introduced in' indicates putting letters inside.
'characteristic' becomes 'trait' (I've seen this before).
'ns' placed within 'trait' is 'TRANSIT'.
(Other definitions for transit that I've seen before include "The process of going or passing - sic . . . . . . . gloria mundi" , "carriage" , "Conveyance of goods or people - tin star (anag)" , "Passage of a planet across the sun's disc" , "Act of passing across" .)