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relentless

American  
[ri-lent-lis] / rɪˈlɛnt lɪs /

adjective

  1. not easing or slackening; maintaining speed, vigor, etc..

    a relentless barrage of bad news.

  2. unyieldingly severe, strict, or harsh.

    a relentless crackdown on human rights.
    Synonyms:
    unyielding, adamant, obdurate, unbending, rigid
    Antonyms:
    merciful
relentless British  
/ rɪˈlɛntlɪs /

adjective

  1. (of an enemy, hostile attitude, etc) implacable; inflexible; inexorable

  2. (of pace or intensity) sustained; unremitting

"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

Related Words

See inflexible.

Other Word Forms

  • relentlessly adverb
  • relentlessness noun

Etymology

Origin of relentless

First recorded in 1585–95; relent + -less

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.