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Synonyms

merciless

American  
[mur-si-lis] / ˈmɜr sɪ lɪs /

adjective

  1. without mercy; having or showing no mercy; pitiless; cruel.

    a merciless critic.

    Synonyms:
    inexorable, unsympathetic, fell, unrelenting, relentless, hard
    Antonyms:
    compassionate

merciless British  
/ ˈmɜːsɪlɪs /

adjective

  1. without mercy; pitiless, cruel, or heartless

"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

Other Word Forms

  • mercilessly adverb
  • mercilessness noun

Etymology

Origin of merciless

First recorded in 1300–50; Middle English mercyles; mercy, -less

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Contemporaries regarded this merciless battle as “a second Agincourt,” akin to Henry V’s victory, against the odds, in 1415.

From The Wall Street Journal

Barely two years in, Maye’s the shiniest star in a merciless sports metropolis—and he’s one Sunday victory from all the local Bradys naming their future firstborns Drake.

From The Wall Street Journal

A moist, merciless heat engulfed us, and the strangling smell forced its way down my nose and throat.

From Literature

The journalist James Agee’s merciless portraits of his subjects remind Mr. Frazier of “those old-time operations that were done on a kitchen table without anesthetic.”

From The Wall Street Journal

They were all failed attempts to impose western civilization on the merciless, untamable Arctic.

From Literature