Like a long journey? Yes, and so must get moving (8)
I believe the answer is:
odyssean
'like a long journey?' is the definition.
(reminiscent of Odysseus' epic journey)
'yes and so must get moving' is the wordplay.
'must get moving' is an anagram indicator.
'yes'+'and'+'so'='yesandso'
'yesandso' is an anagram of 'ODYSSEAN'.
(Other definitions for odyssean that I've seen before include "Like years of wandering" , "Like travels" , "about epic poem" , "epic journey" , "trip involving vessel?" .)