headshake vs headshaking

headshake and headshaking both are nouns.

Word	Noun	Adjective	Verb	Adverb
headshake	Yes	No	No	No
headshaking	Yes	No	No	No

As nouns, headshake and headshaking are synonyms defined as:

headshake and headshaking: the act of turning your head left and right to signify denial or disbelief or bemusement

headshake (noun)	headshaking (noun)
the act of turning your head left and right to signify denial or disbelief or bemusement	the act of turning your head left and right to signify denial or disbelief or bemusement