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beachball

[beech-bawl]
noun
  1. a large, light, buoyant ball, used especially for games at the seashore, swimming pools, etc.

Origin of beachball

First recorded in 1935–40; beach + ball1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for beach ball

beach ball

noun
  1. a large light brightly coloured ball for playing with on a beach
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