Gun the engine (3)
'gun the engine' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for rev that I've seen before include "Minister" , "Gun (an engine)" , "Reverend (abbr.)" , "Speed up engine (colloq.)" , "Clergy title" .)
'gun the engine' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for rev up that I've seen before include "To create excitement" , "Increase the engine speed" , "Accelerate sharply" , "Press accelerator" , "Gun the engine" .)