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clean as a hound's tooth

a. (context simile English) Very clean (very innocent)

Usage examples of "clean as a hound's tooth".

But Admiral Wingate Stantington was going to be as clean as a hound's tooth, and perhaps someday, when they were looking around for viable, clean candidates for offices like President, Wingate Stantington would stand out like a silver dollar atop a pile of pennies.

Did we suppose he could look his Sally Ann straight in the eye, reconciliationwise, or salute the College pennant at the next Junior Enochist cookout, if his conscience weren't clean as a hound's tooth?

Anyone stationed there would have to be as clean as a hound's tooth.