indefatigable, untiring, unstinting, tenacious, unflagging, selfless, diligent, relentless, unwavering, assiduous, unfailing, steadfast, doughty, unswerving, courageous, fearless, valiant, stakhanovite, unyielding, industrious, ceaseless, exemplary, unceasing, indomitable, unsung, unfaltering, perseverant, irrepressible, stalwart, conscientious, dauntless, resolute, ardent, skillful, admirable, undying, hardworking, skilful, passionate, energetic, unrelenting, unselfish, fervent, peerless, heroic, zealous, meticulous, herculean, thankless, vigorous, visionary, pioneering, prodigious, staunch, gallant, redoubtable, wholehearted, unflinching, work ethic, superb, workaholic, ferocious, tigerish, brilliant, eloquent, grateful, spirited, dutiful, lifelong, uncomplaining, intrepid, unabashed, resourceful, crusading, uncompromising, adroit, impassioned, noble, inveterate, canny, impeccable, unrewarded, persevering, painstaking, brave, unflappable, countless, crackerjack, nonpareil, gutsy, invaluable, masterful, inspiring, redoubled, principled, unremitting, commendable, stouthearted, wily, uncelebrated, enterprising, problem solver, cargo, estimations, fraternities, series, steamboats, tempos, traverses, vipers, whirlpool, abject, absolute, accounting, adobes, advanced, advertisers, airline, airlines, allotments, appeals, arsenal, unwearied, unwearying, singleminded, unresting, earnest, sacrificing, dogged

indefatigability, indefatigableness, tirelessness