Turn something on its head (5)
I believe the answer is:
upend
(Other definitions for upend that I've seen before include "Set on side, turn over" , "Flip" , "Knock over" , "Alter greatly" , "Affect drastically" .)
I believe the answer is:
upend
(Other definitions for upend that I've seen before include "Set on side, turn over" , "Flip" , "Knock over" , "Alter greatly" , "Affect drastically" .)