Done by moving the hand (and arm) from below.(adjective)
Sly, dishonest, corrupt, cheating.(adjective)
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Use "underhanded" in a sentence
"Perkins, worn out, irritated by, if not angry at, what he termed the underhanded lying of the opposition, drove home for luncheon, and found his wife and her mother in a state of high dudgeon."
"Frederick and Mary Ann Brussat go a step further in underhanded criticism, comparing the movie to The Lion, the Witch, and the Wardrobe in an apparent attempt to give it a Christian link and then add, "Naturally, a female is one of the main temptations Will must overcome.""
"If the overstuffed, unzipped, unsealed bags contain more absentee ballots than were recorded on the transmittal sheet, then something underhanded is being attempted."