Third-person singular simple present indicative form of thwack. (verb)
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Use "thwacks" in a sentence
"By the same token, the vivid portrayal of the Last Judgment that Verdi incorporated into the "Dies irae" movement of his Requiem, with its minor-key trumpet calls and bomblike thwacks on the bass drum, is as exciting as any of his operas—and as "pictorial" as "Jesus Mocked by the Soldiers.""
"Jackson strikes out, but then Raburn thwacks another home run."
"Ringo drummer Ralph Castelli, for instance, simply "thwacks away in the background, looking appropriately laid-back.""