Synonyms of indefatigable in English:

indefatigable


See US English definition of indefatigable

See UK English definition of indefatigable

See Spanish definition of infatigable

adjective

1‘he is one of those indefatigable researchers who won't take no for an answer’

SYNONYMS
tireless, untiring, never-tiring, unwearied, unwearying, unflagging
energetic, dynamic, enthusiastic
unrelenting, relentless, unremitting, unswerving, unfaltering, unshakeable, indomitable
persistent, tenacious, determined, dogged, single-minded, assiduous, industrious
ANTONYMS

idle, feeble