Caught leg making ascent (5)
I believe the answer is:
climb
'ascent' is the definition.
('climb' can be a synonym of 'ascent')
'caught leg' is the wordplay.
'caught' becomes 'c' (cricket abbreviation).
'leg' becomes 'limb' (I've seen this before).
'c'+'limb'='CLIMB'
'making' acts as a link.
(Other definitions for climb that I've seen before include "Ascend - ascent" , "Go up - scale" , "Rise, mount" , "Rise (in value, status)" , "Soar" .)