Simple Definition of tireless

from our Learner's Dictionary

tireless

adjective

: working very hard with a lot of energy for a long time : never seeming to get tired
He's a tireless worker.
She has been a tireless advocate for reform.

Cite this Entry

“Tireless.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/tireless. Accessed 14 Apr. 2026.

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