adv ·Rare ·Advanced level

Definitions

Adverb

1. 1
   In an extremely persistent and untiring manner; in an indefatigable manner

   "Silence, silence,’ the trumpet mouths indefatigably repeated at intervals down every corridor."

Adverb

1. 1
   with indefatigable energy wordnet

Synonyms

All synonyms

diligentlydoggedlyenergeticallyfaithfullyferventlyhard

Example

More examples

"Silence, silence,’ the trumpet mouths indefatigably repeated at intervals down every corridor."

Etymology

From indefatigable + -ly, but indefatigable itself was attested later. In use since the 16th century.

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.