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

The 25-year-old’s relentless work in the batting cage and weight room has earned him the reputation for being a bit robotic. —Mitch Bannon, New York Times, 21 Mar. 2026

The Wolverines, fired up to play in front of their fans, were relentless at both ends of the court early. —CBS News, 21 Mar. 2026

Motives centers around Detective Izzy Morgan (Vasquez), a relentless investigator pulled into a dark and intricate case that exposes the hidden violence beneath wealth and privilege. —Anthony D'alessandro, Deadline, 20 Mar. 2026

But the relentless words of wisdom, and the shouting-to-the-rafters way they’re delivered, soon become tiresome. —Jon O'Brien, IndieWire, 19 Mar. 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