180, so to speak (1-4)
I believe the answer is:
u-turn
'180 so to speak' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for u-turn that I've seen before include "A complete reverse of direction" , "Complete change of direction" , "Volte-face" , "Complete reversal of car or attitude" , "Complete reverse movement as by car" .)