The act of shaking one's head, in disagreement or disapproval(noun)
Disagreement or disapproval(noun)
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Use "headshaking" in a sentence
"There is, however, a fine line, a careful balance, between communicating inspiration and enthusiasm, and generating the kind of headshaking and 'blistering comments' Greer picked up at the back of the hall."
"More and more, I think this is the answer to all the truly headshaking things I see coming out of the left."
"You have the optimism of Bill Richards and the fingers-in-the-ears headshaking of Peter Kafka."