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underdog

American  
[uhn-der-dawg, -dog] / ˈʌn dərˌdɔg, -ˌdɒg /

noun

  1. a person who is expected to lose in a contest or conflict.

  2. a victim of social or political injustice.

    The underdogs were beginning to organize their protests.
underdog British  
/ ˈʌndəˌdɒɡ /

noun

  1. the competitor least likely to win a fight or contest

  2. a person in adversity or in a position of inferiority

"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 underdog

1875–80, under- + dog ( def. )

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.