Sekirov Dictionary

give one's head a shake

verb1

•
(Canada) To reassess the common sense of one's behaviour, ideas, etc.
- If you're thinking about topping your burger with ketchup, mustard, relish and perhaps a couple of pickle slices, you might want to "give your head a shake." — 2009

forms

gave one's head a shake · given one's head a shake · giving one's head a shake · gives one's head a shake

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