Has Jesse lost energy? (4)
I believe the answer is:
owns
'has' is the definition.
('own' can be a synonym of 'have')
'jesse lost energy?' is the wordplay.
'jesse' becomes 'Owens' (Jessie Owens Olympic sprinter 1936).
'lost' indicates named letters should be taken away.
'energy?' becomes 'e' (physics symbol as in E=mc2).
'owens' with 'e' removed is 'OWNS'.
(Other definitions for owns that I've seen before include "Possesses" , "uses" , "Admits possession" , "Belongs to" , "Confesses" .)