Clear off! (3,2)
'clear off' is the definition.
(both can be used to tell someone to go away)
This is all the clue.
(Other definitions for scram that I've seen before include "make emergency shut-down" , "Bolt" , "Scarper" , "Vamoose" , "Make oneself scarce" .)
(Other definitions for hop it that I've seen before include "split" , "get out quick!" , "Get away!" , "Skedaddle!" , "Scram!" .)