Heads out (6)
'heads out' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for goes that I've seen before include "See 17" , "Disappears; runs" , "See 4" , "Departs; operates" , "SECOND PART OF 21" .)
(Other definitions for leaves that I've seen before include "Departs with book pages?" , "takes off" , "''All the ... are brown'' (California Dreamin')" , "Organs of photosynthesis" , "Steps out of" .)