indefatigable

2 antonyms for indefatigable — opposites grouped by meaning.

Adj — Never getting tired, however long or hard the effort.

Antonyms

idle indolent

Came into English via Middle French, from Latin indēfatīgābilis (“untiring”), from in- (“not”) + dēfatīgō (“to tire out”).

idle tireless indolent unflagging unwearying