Social climber out of bed to get going (7)
I believe the answer is:
upstart
'social climber' is the definition.
(term for someone seeking higher social status)
'out of bed to get going' is the wordplay.
'out of bed' becomes 'up' (synonyms).
'to get going' becomes 'start' ('start' can be a synonym of 'get going').
'up'+'start'='UPSTART'
(Other definitions for upstart that I've seen before include "Arrogant Johnny-come-lately" , "Tap rust (anag.)" , "Social climber or wise guy" , "Arrogant person new in high position" , "Person suddenly risen in world, and arrogant" .)