indefatigable

Indefatigable in those two roles, he hankered after others, as well.

It is easy to speak of his ability, of his sagacity, of his indefatigable industry.

The intellect, moreover, becomes wearied, while Will is indefatigable.

Their indefatigable unobtrusiveness, their kindly, faithful service I both dread and appreciate.

The former, as commodore, hoisted his pennant on the Indefatigable, the latter on the Rvolutionaire.

This was indeed glad tidings to the indefatigable detective, and he could have caressed the graceful little animal from pure joy.