Very masculine, retaining current energy (3)
I believe the answer is:
vim
'energy' is the definition.
(I know that energy can be written as vim)
'very masculine retaining current' is the wordplay.
'very' becomes 'v' (abbreviation).
'masculine' becomes 'm'.
'retaining' means one lot of letters goes inside another (inserted letters are held or retained).
'current' becomes 'I' (symbol for electric current).
'v'+'m'='vm'
'vm' placed around 'i' is 'VIM'.
(Other definitions for vim that I've seen before include "Energy, enthusiasm" , "Liveliness" , "Pep and energy" , "Informal energy or drive" , "Pep (informal)" .)