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jacks

British  
/ dʒæks /

noun

  1. Sometimes called: knucklebones(functioning as singular) a game in which bone, metal, or plastic pieces ( jackstones ) are thrown and then picked up in various groups between bounces or throws of a small ball

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of jacks

C19: shortened from jackstones , variant of checkstones pebbles

Explanation

Jacks is a children's game in which you bounce a small ball and quickly scoop up game pieces. There's evidence that some form of jacks was even played in ancient Greece. Jacks goes by many names, including "knucklebones" and "fivestones." The original version was played with small stones, which were closely related to dice, and invented around the same time. In modern jacks, a player drops ten metal star-shaped pieces and then tries to scoop them up — first one at a time, then two at a time, and so on — after bouncing a ball, which is then caught before it hits the ground.

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Vocabulary lists containing jacks

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“It’s like a hydraulic system. It really is very much like the jacks that push your car up, or something that an excavator might have,” Drew said.

From Los Angeles Times • May 7, 2026

That includes Iran, which is straining under a historic drought made worse by years of mismanagement, while climate change jacks up temperatures and reduces rainfall.

From Salon • Mar. 17, 2026

A lonely coyote stalks the barren ground around oil pump jacks; a dead deer, its eye milky white, lies on a fern-like blanket of boughs.

From The Wall Street Journal • Feb. 27, 2026

Watching young Reiner play jacks in the living room, he thought the kid was hilarious.

From Los Angeles Times • Dec. 15, 2025

I stared at the flat poker faces of the kings and jacks and queens and listened to the nurse talking about her hard life.

From "The Bell Jar" by Sylvia Plath