The characteristic of deceptiveness; duplicity; untruthfulness.(noun)
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Use "forked tongue" in a sentence
"The demon climbed out the window and across the front, where he perched like a hood ornament from hell, his forked tongue flying in the wind like a storm-swept pennon, spattering the windshield with saliva."
"It clattered to the floor, barely missing the lizardlike tail of another godboy, who flicked his forked tongue in annoyance at him and then scuttled away."
"He twisted his body into winding folds, and darted out his forked tongue with frightful hissings."