Scale, ascend (5)
I believe the answer is:
climb
This clue is a double definition.
'scale' is the first definition.
(I know that scale is a more specific form of the action climb)
'ascend' is the second definition.
(climbing is a kind of ascending)
(Other definitions for climb that I've seen before include "Rise (in value, status)" , "Ascend, scale" , "Ascend, escalate" , "Walk up" , "Go up - scale" .)