Stout with energy in significantly reduced supply (8)
I believe the answer is:
fearless
'stout' is the definition.
(thesaurus)
'energy in significantly reduced supply' is the wordplay.
'energy' becomes 'e' (physics symbol as in E=mce).
'in' indicates putting letters inside.
'significantly' becomes 'far' (I've seen this in another clue).
'reduced supply' becomes 'less' (I can't explain this - if you can you should give a lot more credence to this answer).
'e' put within 'far' is 'fear'.
'fear'+'less'='FEARLESS'
'with' is the link.
Can you help me to learn more?
(Other definitions for fearless that I've seen before include "Stout-hearted" , "Ignoring danger and peril" , "Totally courageous" , "Bold" , "Not afraid" .)