Right measure of current inclination (4)
I believe the answer is:
ramp
'inclination' is the definition.
(an inclined surface)
'right measure of current' is the wordplay.
'right' becomes 'r' (common abbreviation).
'measure of current' becomes 'amp' (I've seen this in another clue).
'r'+'amp'='RAMP'
(Other definitions for ramp that I've seen before include "Slope between levels" , "Level-connecting slope" , "Slope - racket" , "Wheelchair access?" , "Incline" .)