relentless

adjective

re·​lent·​less ri-ˈlent-ləs 

: showing or promising no abatement of severity, intensity, strength, or pace : unrelenting

relentless pressure

a relentless campaign

relentlessly adverb

relentlessness noun

Synonyms of relentless

• grim
• determined
• persistent
• unrelenting
• ruthless

Examples of relentless in a Sentence

Her relentless optimism held the team together.

The hunter was relentless in pursuit of his prey.

a relentless opponent of deregulation

Recent Examples on the Web

Castle has particularly been fantastic, with 18 points while making 7 of his 8 shots, and he's been relentless at getting into the paint using patient drives. —Andrew Greif, NBC news, 9 June 2026

While the combination of editor Sarah Broshar’s relentless pacing and John Williams’ full-bodied score (which stands among the veteran composer’s finest) makes for an exciting watch throughout, the breathless action sequences are especially thrilling. —David Rooney, HollywoodReporter, 9 June 2026

That new reality is the result of Iran’s relentless efforts to link the fate of both conflicts, and of the increasingly diverging priorities of the US president and the Israeli prime minister. —Jeremy Diamond, CNN Money, 9 June 2026

Wembanyama said San Antonio had been relentless but needed to turn that effort into something more tangible. —C.j. Holmes, New York Daily News, 8 June 2026

Word History

First Known Use

1592, in the meaning defined above

Kids Definition

relentless

adjective

re·​lent·​less ri-ˈlent-ləs 

: not lessening in severity, intensity, strength, or pace : unrelenting

relentless criticism

relentlessly adverb

relentlessness noun