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

In non-linear lyric forms, the following collections braid love’s ruthless endings with its tenderest beginnings. — Literary Hub, 17 Sep. 2026

Meanwhile, third wife Iya Femi (Bimbo Ademoye) is the most cunning and ruthless in trying to defend her position within the household, playing up to Iya Segi’s schemes as her most willing conspirator. — Murtada Elfadl, Variety, 16 Sep. 2026

From here, Clementine becomes two distinct characters, both the girl Ridgeway met in real life (and will meet again in the local town) and prey for the ruthless Tom Ripley in Highsmith’s developing fiction. — Damon Wise, Deadline, 15 Sep. 2026

Arsenal created more than enough to help themselves to a bunch of goals in Naples, only to get stuck in anti-ruthless mode. — Amy Lawrence, New York Times, 9 Sep. 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

Kids Definition

ruthless

adjective

ruth·​less ˈrüth-ləs 

: having no pity : merciless, cruel

ruthlessly adverb

ruthlessness noun