A right bounder beginning to escape from passageway (6)
I believe the answer is:
arcade
'passageway' is the definition.
(arcade is a kind of passageway)
'a right bounder beginning to escape' is the wordplay.
'a right' becomes 'ar' (I've seen this in other clues**).
'bounder' becomes 'cad' ('cad' can be a synonym of 'bounder').
'beginning to' says to take the initial letters.
The initial letter of 'escape' is 'e'.
'ar'+'cad'+'e'='ARCADE'
'from' acts as a link.
(Other definitions for arcade that I've seen before include "Here one may find shops" , "Covered way with shops on either side" , "Covered walk with shops" , "shopping precinct" , "Covered passage containing shops" .)