Loser energetically gets calm (6)
I believe the answer is:
serene
'calm' is the definition.
(I know that calm can be written as serene)
'loser energetically gets' is the wordplay.
'gets' says the answer is hidden in the clue.
'SERENE' is hidden within 'loser energetically'.
(Other definitions for serene that I've seen before include "Placid" , "Tranquil, perfectly calm" , "without any trouble" , "Fair" , "Calm and unclouded" .)