Significant empowerment, but somewhat reduced speed (5)
I believe the answer is:
tempo
'speed' is the definition.
(I've seen this before)
'significant empowerment but somewhat reduced' is the wordplay.
'somewhat reduced' indicates the answer is hidden within the clue.
'TEMPO' is hidden within 'significant empowerment but'.
(Other definitions for tempo that I've seen before include "Metronome output" , "Pace of a musical piece" , "Speed of 3A" , "Cadence" , "Rhythm or speed as in music" .)