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

The tension comes from Odd Henderson, a schoolyard bully and tireless tormentor of Buddy, a character based on the young Capote.

Read more on The Wall Street Journal

Ecke Jr. also had a reputation as a tireless promoter, further cementing the poinsettia-Christmas connection with magazine shoots and giving TV stations free poinsettias to decorate late-night talk shows or holiday specials.

Read more on Los Angeles Times

Thanks to the tireless efforts of Mrs. Clarke, the baby’s room is nearly finished, and surely that is well worth a look.

Read more on Literature

The soaring red kites, with their broad and tireless wings?

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The charity said since then he had been a "tireless advocate".

Read more on BBC

Related Words

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