Energy, determination (6)
I believe the answer is:
spirit
I believe this is a double definition.
'energy' is the first definition.
(I've seen this before)
'determination' is the second definition.
(I've seen this before)
(Other definitions for spirit that I've seen before include "Soul - ethos" , "Ghost or strong drink" , "Wraith" , "Animation or energy" , "Drink for a supernatural being" .)