Passage shortly starting off (7)
I believe the answer is:
transit
'passage' is the definition.
('transit' can be a synonym of 'passage')
'shortly starting off' is the wordplay.
'shortly' means to remove the last letter.
'off' indicates anagramming the letters.
'starting' with its final letter taken off is 'startin'.
'startin' anagrammed gives 'TRANSIT'.
(Other definitions for transit that I've seen before include "Haulage" , "Passage of a planet across the sun's disc" , "Passage of planet across the disc of the sun" , "Pass through; van" , "Pass across/through" .)