Walks into space, possibly (5)
I believe the answer is:
paces
'walks' is the definition.
(pacing is a kind of walking)
'space possibly' is the wordplay.
'possibly' indicates anagramming the letters.
'space' anagrammed gives 'PACES'.
'into' is the link.
(Other definitions for paces that I've seen before include "Steps or strides" , "Single steps" , "Space for steps" .)