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flutterboard

American  
[fluht-er-bawrd, -bohrd] / ˈflʌt ərˌbɔrd, -ˌboʊrd /

noun

  1. a kickboard.


flutterboard British  
/ ˈflʌtəˌbɔːd /

noun

  1. Brit word: float.  an oblong board or piece of polystyrene plastic used by swimmers in training or practice

"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 flutterboard

First recorded in 1945–50; flutter + board