tire·​less | \ˈtī(-ə)r-ləs \

Definition of tireless 

: seemingly incapable of tiring : indefatigable a tireless worker

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Other Words from tireless

tirelessly adverb
tirelessness noun

Examples of tireless in a Sentence

She has been a tireless advocate for reform. a tireless advocate for human rights

Recent Examples on the Web

The two chatted about everything from motherhood after #MeToo to politics and Stone's tireless work in HIV/AIDS activism. Amanda Mitchell, Marie Claire, "Sharon Stone on Being a Mom to Sons in a Post-MeToo World," 16 Oct. 2018 Bill's passion for the arts was felt by all who knew him, and his warmth and tireless energy were undeniable. Fox News, "Bill Paxton's surgeon, hospital deny responsibility for his death," 2 Oct. 2018 But its disappearance left behind a compelling mystery, one kept in the public consciousness for years by the tireless efforts of Franklin’s widow. Kiona N. Smith, Ars Technica, "Strands of hair shed light on doomed 19th-century Arctic expedition," 30 Sep. 2018 Under his tireless leadership, Sunroof of Florida quickly became a strong and profitable business, ultimately expanding into a second location in Jacksonville. Sun-Sentinel.com, "Deaths in South Florida: 2/6," 6 Feb. 2018 Li and Yan said Chiang was a tireless supporter of their work. Kevin Truong /, NBC News, "New pop-rock poetry musical shines a spotlight on queer Asian-Americans," 9 July 2018 Sonia Russell Lieutenant Sonia Russell, demonstrates outstanding leadership and tireless effort in addressing the organizational improvement, community enrichment and professional development. Brandon Patterson, Detroit Free Press, "How these 20 women are protecting Detroiters every day," 23 May 2018 Bourdain was a tireless advocate for his girlfriend and the #MeToo movement and went to great lengths to keep the story in the press using his social-media platforms and his connections. Kenzie Bryant, Vanities, "Asia Argento on Anthony Bourdain: “He Was My Love, My Rock, My Protector”," 8 June 2018 Manchester dedicated an island along the Hockanum River in honor of the late Doug Smith, a tireless advocate of the waterway and its trail system. Peter Marteka, courant.com, "An Island Tribute For Trailblazer Doug Smith," 3 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tireless.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of tireless

1591, in the meaning defined above

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Dictionary Entries near tireless

tire chain


tire gage



tire of

tire press

Statistics for tireless

Last Updated

30 Nov 2018

Look-up Popularity

Time Traveler for tireless

The first known use of tireless was in 1591

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More Definitions for tireless



English Language Learners Definition of tireless

: working very hard with a lot of energy for a long time : never seeming to get tired


tire·​less | \ˈtīr-ləs \

Kids Definition of tireless

: able to work or persist a long time without becoming tired

Other Words from tireless

tirelessly adverb

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More from Merriam-Webster on tireless

Rhyming Dictionary: Words that rhyme with tireless

Thesaurus: All synonyms and antonyms for tireless

Spanish Central: Translation of tireless

Nglish: Translation of tireless for Spanish Speakers

Britannica English: Translation of tireless for Arabic Speakers

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to enclose within walls

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