Moving up when about to come to conclusion (9)
I believe the answer is:
ascending
'moving up' is the definition.
('ascend' can be a synonym of 'move up')
'when about to come to conclusion' is the wordplay.
'when' becomes 'as'.
'about' becomes 'c' (abbreviation for 'circa'**).
'to come to' is a charade indicator (letters next to each other).
'conclusion' becomes 'ending' ('ending' can be a synonym of 'conclusion').
'as'+'c'+'ending'='ASCENDING'
(Other definitions for ascending that I've seen before include "Getting up" , "Rising" , "Going up" .)