Weariless(a.) Incapable of being wearied.
Thesaurus Entries
advertent, agog, alert, all ears, all eyes, ardent, attentive, aware, careful, concentrated, conscious, constant, continuing, diligent, dogged, earnest, elaborate, enduring, energetic, faithful, fervent, finical, finicking, finicky, hard, hardworking, heedful, immutable, inalterable, indefatigable, indomitable, industrious, insistent, intense, intent, intentive, invincible, laborious, lasting, loyal, meticulous, mindful, never idle, never-tiring, nice, niggling, observant, observing, obstinate, on the ball, on the job, open-eared, open-eyed, openmouthed, operose, painstaking, patient, patient as Job, permanent, perseverant, persevering, persistent, persisting, pertinacious, plodding, plugging, preoccupied, rapt, regardful, relentless, resolute, sedulous, single-minded, sleepless, slogging, stable, steadfast, steady, strenuous, stubborn, tenacious, thorough, thoroughgoing, tireless, unabating, unconquerable, undaunted, undiscouraged, undrooping, unfailing, unfaltering, unflagging, unflinching, unintermitting, uninterrupted, unnodding, unrelaxing, unrelenting, unremitting, unsleeping, unsparing, unswerving, untiring, unwavering, unwearied, unwearying, unwinking, utterly attentive, vehement, watchful, weariless, zealous