tireless

[tahyuhr-lis]

adjective

1. never seeming to tire; not slackening: his tireless efforts.

   a tireless worker;

   his tireless efforts.

   Synonyms: unfaltering, hardworking, industrious, unwearied

tireless

/ ˈtaɪəlɪs /

adjective

1. unable to be tired; indefatigable

Other Word Forms

• tirelessly adverb
• tirelessness noun

Word History and Origins

Origin of tireless¹

First recorded in 1585–95; tire ¹ + -less

Example Sentences

Thanks largely to the tireless work of his son, Powers was awarded the Silver Star by the Air Force in 2012.

Read more on Literature

The tireless robot continued north, on and on, toward the waters where the Ancient Shark roamed.

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But it was his tireless daily routine of taking infield grounders, and his ability to learn from and overcome early-season growing pains, that made that moment possible.

Read more on Los Angeles Times

The city was a glittering modern metropolis, where humans lived in luxury, all thanks to the tireless work of robots.

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Graffiti artist, enthusiast and ex-social worker John Nation is known as the godfather of the urban art movement for his tireless dedication and love to the scene.

Read more on BBC

Related Words

• energetic 
• enthusiastic 
• indefatigable 
• resolute 
• steadfast 
• strenuous 
• unflagging 
• vigorous