indefatigable

adjective

in·​de·​fat·​i·​ga·​ble ˌin-di-ˈfa-ti-gə-bəl 

: incapable of being fatigued : untiring

an indefatigable worker

indefatigability

ˌin-di-ˌfa-ti-gə-ˈbi-lə-tē 

noun

indefatigableness

ˌin-di-ˈfa-ti-gə-bəl-nəs 

noun

indefatigably

ˌin-di-ˈfa-ti-gə-blē 

adverb

Synonyms

• inexhaustible
• tireless
• unflagging
• untiring
• weariless

Examples of indefatigable in a Sentence

a person of indefatigable patience

an indefatigable laborer who can work from sunrise to sunset

Recent Examples on the Web

This is coupled with its New Deal for Working People, overseen by indefatigable deputy leader Angela Rayner, which is seeking to overhaul the gig economy and its various precarities. —Max Goldbart, Deadline, 5 July 2024

Furthermore, competitiveness and an indefatigable motor are the major draws for Harkins and Meyer. —Andrew Knoll, Orange County Register, 3 July 2024

Ali: Alfred Russel Wallace’s Right-Hand Gun Wallace wouldn't have become a famous naturalist without help from colonial networks and hundreds of locals, including his indefatigable Sarawak servant, Ali. —JSTOR Daily, 24 June 2024

Good thing 93-year-old Thelma (an indefatigable June Squibb) is no softie. —Eric Andersson, Peoplemag, 21 June 2024

Word History

Etymology

Middle French, from Latin indefatigabilis, from in- + defatigare to fatigue, from de- + fatigare to fatigue

First Known Use

1608, in the meaning defined above

Kids Definition

indefatigable

adjective

in·​de·​fat·​i·​ga·​ble ˌin-di-ˈfat-i-gə-bəl 

: capable of working a long time without tiring : tireless

an indefatigable teacher

indefatigably

-blē 

adverb