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Hacky Sack

American  
[hak-ee] / ˈhæk i /

  1. a brand of footbag.

noun

  1. (lowercase) a game in which a footbag is juggled with the feet.

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.