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

• affectless
• callous
• case-hardened
• cold-blooded
• compassionless
• desensitized
• hard
• hard-boiled
• hard-hearted
• heartless
• indurate
• inhuman
• inhumane
• insensate
• insensitive
• ironhearted
• merciless
• obdurate
• pachydermatous
• pitiless
• remorseless
• slash-and-burn
• soulless
• stony
• stoney
• stonyhearted
• take-no-prisoners
• thick-skinned
• uncharitable
• unfeeling
• unmerciful
• unsparing
• unsympathetic

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

Russo, who has avoided serious injury and is set to return to play for Arsenal this month, is an out-and-out centre-forward, a grafter who uses her strength to take care of the ball and stitch play, but is also becoming a more ruthless penalty-box striker. —Charlotte Harpur, New York Times, 9 Apr. 2025

The way to move up in your organization might require being ruthless. —Roberta Matuson, Forbes.com, 9 Apr. 2025

But when the ruthless Mafia boss Nicola Grimaldi discovers his young son has been kidnapped and murdered, the suspect and Grimaldi’s former friend Vito seeks refuge with police. —Leo Barraclough, Variety, 9 Apr. 2025

Reunited with his godson (Finn), a street-level enforcer tied to a criminal syndicate, the two forge an uneasy alliance and plot a high-stakes heist to escape the grip of a ruthless mob boss. —Andreas Wiseman, Deadline, 7 Apr. 2025

Word History

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