Indefatigable and Sluggish

Indefatigable

Indefatigable adjective - Showing no signs of weariness even after long hard effort.
Usage example: an indefatigable laborer who can work from sunrise to sunset

Sluggish is an antonym for indefatigable.

Sluggish

Sluggish adjective - Moving or proceeding at less than the normal, desirable, or required speed.

Indefatigable is an antonym for sluggish.

Nearby Words: sluggishness, sluggishly
Cite this Source
Sluggish and Indefatigable. (2016). Retrieved 2026, August 15, from https://thesaurus.plus/related/indefatigable/sluggish
Indefatigable & Sluggish. N.p., 2016. Web. 15 Aug. 2026. <https://thesaurus.plus/related/indefatigable/sluggish>.
Sluggish or Indefatigable. 2016. Accessed August 15, 2026. https://thesaurus.plus/related/indefatigable/sluggish.
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