Man perhaps following a narrow passage (5)
I believe the answer is:
aisle
'narrow passage' is the definition.
(I've seen this in another clue)
'man perhaps following a' is the wordplay.
'man perhaps' becomes 'isle' (Isle of Man is an example).
'following' is a charade indicator (letters next to each other).
'isle' put after 'a' is 'AISLE'.
(Other definitions for aisle that I've seen before include "Passage between rows of seats" , "Supermarket section" , "Way between seat blocks" , "Passage between seating blocks" , "Passageway between pews" .)