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Synonyms

ruthless

American  
[rooth-lis] / ˈruθ lɪs /

adjective

  1. without pity or compassion; cruel; merciless.

    a ruthless tyrant.

    Synonyms:
    relentless, adamant, unrelenting

ruthless British  
/ ˈruːθlɪs /

adjective

  1. feeling or showing no mercy; hardhearted

"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 cruel.

Other Word Forms

  • ruthlessly adverb
  • ruthlessness noun

Etymology

Origin of ruthless

First recorded in 1300–50; Middle English; ruth + -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.

Ursula has shades of Gellar’s famous characters — Buffy’s physical ferocity, Kathryn Merteuil’s ruthless cattiness, Daphne Blake’s affinity for mysterious games — but doesn’t play to one exclusively.

From Salon • Mar. 26, 2026

Ghalibaf is considered ruthless and ambitious but also a competent manager.

From The Wall Street Journal • Mar. 25, 2026

David Plotz: Do you get the sense that Lachlan has the ruthless brilliance and the eye for talent that Rupert Murdoch has had?

From Slate • Mar. 21, 2026

Van Geelen’s test is ruthless: If an AI agent can do it for you, a company’s competitive edge was never its technology.

From MarketWatch • Mar. 19, 2026

“Our only chance is clever bargaining. Cliff trolls are cunning and ruthless, but their avarice can be a weakness.”

From "Fablehaven" by Brandon Mull