Pretentious person rose up awkwardly (6)
I believe the answer is:
poseur
'pretentious person' is the definition.
(I've seen this before)
'rose up awkwardly' is the wordplay.
'awkwardly' is an anagram indicator.
'rose'+'up'='roseup'
'roseup' with letters rearranged gives 'POSEUR'.
(Other definitions for poseur that I've seen before include "Pretentious person" , "Attitudiniser (Fr.)" , "Exhibitionist" , "Uprose (anag.)" , "Pretentious type" .)