Definitions

merciless

[mur-si-lis] / ˈmɜr sɪ lɪs /

ADJECTIVE

mean, heartless

Synonyms

STRONGEST

barbarous callous cruel fierce grim harsh implacable inexorable inhumane relentless ruthless severe unforgiving unrelenting unsparing unyielding

STRONG

unmerciful

WEAK

compassionless cutthroat dog-eat-dog gratuitous hard hardhearted hatchet job having a killer instinct iron-fisted mean machine mortal pitiless unappeasable uncalled-for unfeeling unflinching unpitying unsympathetic wanton

Antonyms

STRONGEST

bright calm compassionate considerate easy feeling flexible gentle kind merciful mild nice peaceful polite remorseful sympathetic tender yielding

WEAK

giving sparing

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.

He was exacting, charming and merciless in equal measure.

From BBC • Apr. 10, 2026

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 • Feb. 11, 2026

The 1972 peak was followed by a merciless recession in the mid-1970s, and a heartbreaking stock market bust.

From Barron's • Dec. 31, 2025

Unlike, for example, Molly Jong-Fast’s merciless “How to Lose Your Mother,” “Bad Bad Girl” doesn’t read like a hit job.

From Los Angeles Times • Oct. 17, 2025

The advance of Lola’s dominion was merciless and made self-pity irrelevant.

From "Atonement" by Ian McEwan

Vocabulary lists containing merciless

Hamilton

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Schooled

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Theodore Roosevelt on "The Man with the Muck Rake" (1906)

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