Space man follows marsupial (4)
I believe the answer is:
room
'space' is the definition.
(enough space or room to do something)
'man follows marsupial' is the wordplay.
'man' becomes 'm' (M is an abbreviation for male or masculine).
'follows' is a charade indicator (letters next to each other).
'marsupial' becomes 'roo' (short for kangaroo).
'm' put after 'roo' is 'ROOM'.
(Other definitions for room that I've seen before include "kitchen?" , "Space (for elbows?)" , "bedsit?" , "Capacity" , "Enclosed space in a building" .)