Men on acid lost control (9)
I believe the answer is:
dominance
'control' is the definition.
(dominance is a kind of control)
'men on acid lost' is the wordplay.
'lost' indicates an anagram.
'men'+'on'+'acid'='menonacid'
'menonacid' anagrammed gives 'DOMINANCE'.
(Other definitions for dominance that I've seen before include "Ascendancy" , "Control - ascendency" , "Power (over others)" , "Commanding position" , "Supremacy" .)