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

For the British in North America, the war begun in 1754 had included a series of defeats, a relentless struggle against people who knew the terrain and who linked arms with the French. —Literary Hub, 26 May 2026

Their relentless work ethic improves our team daily. —Zack Cox, Boston Herald, 26 May 2026

The breakthroughs that reshape industries, create new markets and redefine human possibility usually emerge from relentless, uncomfortable and often inconvenient questioning. —David Henkin, Forbes.com, 26 May 2026

The Minnetonka native has playmaking ability, is relentless on the forecheck and plays a two-way game. —Michael Russo, New York Times, 26 May 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