gnash one's teeth

Idioms  

1. Express a strong emotion, usually rage, as in When Jonah found out he was not going to be promoted, he gnashed his teeth. This expression is actually redundant, since gnash means “to strike the teeth together.” Edmund Spenser used it in The Faerie Queene (1590): “And both did gnash their teeth.” [Late 1500s]

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Example Sentences

Her insulting taciturnity was enough sometimes to make one gnash one’s teeth with rage. 

From 'Twixt Land and Sea by Conrad, Joseph

But at times energy failed and one felt inclined to gnash one's teeth at the futility of it all.

From Caught by the Turks by Yeats-Brown, Francis