Social climber puts off painting (7)
I believe the answer is:
upstart
'social climber' is the definition.
(term for someone seeking higher social status)
'puts off painting' is the wordplay.
'off' is an anagram indicator.
'painting' becomes 'art' (painting is an art).
'puts' with letters rearranged gives 'upst'.
'upst'+'art'='UPSTART'
(Other definitions for upstart that I've seen before include "Arrogant person new in high position" , "Arrogant Johnny-come-lately" , "mushroom" , "Presumptuous and arrogant type" , "Person who has risen quickly, and arrogant with it" .)