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baseball cap

noun
  1. a close-fitting cap with a deep visor and usually the name or emblem of a baseball team, worn by baseball players, or by others as casual attire.
Also called ball cap.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for ball cap

baseball cap

noun
  1. a close-fitting thin cap with a deep peak
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