ruthless

adjective

ruth·​less ˈrüth-ləs 

also ˈru̇th-

: having no pity : merciless, cruel

a ruthless tyrant

ruthlessly adverb

ruthlessness noun

Did you know?

If someone can be ruthless, can one also be ruthful?

Ruthless can be defined as "without ruth" or "having no ruth." So what, then, is ruth? The noun ruth, which is now considerably less common than ruthless, means "compassion for the misery of another," "sorrow for one's own faults," or "remorse." And, just as it is possible for one to be without ruth, it is also possible to be full of ruth. The antonym of ruthless is ruthful, meaning "full of ruth" or "tender." Ruthful can also mean "full of sorrow" or "causing sorrow." Ruth can be traced back to the Middle English noun ruthe, itself from ruen, meaning "to rue" or "to feel regret, remorse, or sorrow."

Synonyms of ruthless

• merciless
• stony

Examples of ruthless in a Sentence

The journalist was ruthless in his criticism.

an office supervisor with a ruthless disregard for others' feelings

Recent Examples on the Web

Communism’s pure economic theory is now rarely practiced anywhere — even if ruthless leaders in hybrid capitalist economies like China and Russia have retained the authoritarian iron fists of their predecessors. — Harmeet Kaur, CNN Money, 8 July 2026

Otherwise, Kail sticks closely to the template established for him, recreating every scene and sequence from the first movie with ruthless fidelity and adding essentially no departures of any significance. — Wilson Chapman, IndieWire, 8 July 2026

Erivo plays a British defense barrister who exudes enviable brilliance in navigating the ruthless and gladiatorial London courtrooms. — Anthony D'alessandro, Deadline, 7 July 2026

Standing in their way is Marco (Will Kemp), a powerful and ruthless commander who also happens to be Balaban's brother, the two men now on a collision course shaped by old wounds and irreconcilable choices. — Veronica Villafañe, Forbes.com, 7 July 2026

Word History

Etymology

Middle English rewthles, routheeles, from rewthe, routhe "pity, ruth" + -les -less

First Known Use

14th century, in the meaning defined above

Rhymes for ruthless

• toothless

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Kids Definition

ruthless

adjective

ruth·​less ˈrüth-ləs 

: having no pity : merciless, cruel

ruthlessly adverb

ruthlessness noun