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earmuff

[eer-muhf]
noun
  1. either of a pair of often adjustable coverings for protecting the ears in cold weather.

Origin of earmuff

An Americanism dating back to 1855–60; ear1 + muff
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for earmuff

earmuff

noun
  1. one of a pair of pads of fur or cloth, joined by a headband, for keeping the ears warm
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