Transport bound for moon? Small steps with it? (9)
I believe the answer is:
spaceship
'transport bound for moon?' is the definition.
(a spaceship might be heading to the moon)
'small steps with it?' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'steps' becomes 'paces' (pace is a kind of step).
'with it?' becomes 'hip' (I've seen this before).
's'+'paces'+'hip'='SPACESHIP'
(Other definitions for spaceship that I've seen before include "Craft for an astronaut" , "Interplanetary craft" , "Challenger possibly" , "orbiter, perhaps" , "long-distance traveller?" .)