knave

a deceitful and unreliable scoundrel

A boy; especially, a boy servant.

Old French: knaveux (naughty)

“We require, I said, a protection that the polite world of Great Britain does not now afford us against the aggressions of the knave, the fool, and the brute.”

— George Meredith, Complete Project Gutenberg Works of George Meredith

In Beirut's bustling markets, Ravi thought he found a treasure—until the so-called "guide," a knave in polished shoes, swiped his wallet and vanished into the crowd. Ravi learned that day to beware shiny baubles and silver-tongued scoundrels.

In the Chandni Chowk market of Bangalore, Mehmet carefully counted out five rupees to a street vendor for a masala dosa. The vendor, with a sly grin, pocketed the money and handed Mehmet just half the agreed amount of delicious pancakes, revealing himself as a true knave.

“The ranks (from highest to lowest in bridge and poker) are ace, king, queen, jack (or knave), and the numbers from ten down to two (or deuce).”