Try Our Apps


Supposedly vs. Supposably


[tahyuh r-lis] /ˈtaɪər lɪs/
untiring; indefatigable:
a tireless worker.
Origin of tireless
1585-95; tire1 + -less
Related forms
tirelessly, adverb
tirelessness, noun
unwearied, industrious, hardworking, unfaltering. Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
Cite This Source
Examples from the Web for tireless
Contemporary Examples
Historical Examples
  • All the best work is done this way by tiny, tireless and regular additions, preserving in memory what you think and see.

    Lafcadio Hearn Nina H. Kennard
  • The officers, haggard but tireless, aroused them frequently.

    The Story of the Malakand Field Force Sir Winston S. Churchill
  • In each memory of her he felt the fresh assault of a new and tireless foe—the love which he must deny.

    Satan Sanderson Hallie Erminie Rives
  • He is tireless, and composed as to wrist and shoulder of a number of whale-bone springs.

    The Forest Stewart Edward White
  • Slowly, as though his tireless limbs had grown suddenly old, Spurrier mounted and rode on with reins hanging.

British Dictionary definitions for tireless


unable to be tired; indefatigable
Derived Forms
tirelessly, adverb
tirelessness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Cite This Source
Word Origin and History for tireless

1590s, "indefatigable," from tire (v.) + -less. From 1862 in the sense "without a tire," from tire (n.). Related: Tirelessly.

Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source

Word of the Day

Difficulty index for tireless

Many English speakers likely know this word

Word Value for tireless

Scrabble Words With Friends

Nearby words for tireless