Laborious

a.	1.	Requiring labor, perseverance, or sacrifices; toilsome; tiresome. Dost thou love watchings, abstinence, or toil, Laborious virtues all? Learn these from Cato. - Addison.
	2.	Devoted to labor; diligent; industrious; as, a laborious mechanic.

Adj.

1.

laborious - characterized by toilsome effort to the point of exhaustion; especially physical effort; "worked their arduous way up the mining valley"; "a grueling campaign"; "hard labor"; "heavy work"; "heavy going"; "spent many laborious hours on the project"; "set a punishing pace" Synonyms: arduous, backbreaking, grueling, gruelling, toilsome, punishing, hard, heavy

Herculean, abstruse, ardent, arduous, assiduous, backbreaking, brutal, careful, complex, critical, crushing, delicate, demanding, detailed, determined, difficile, diligent, dogged, effortful, energetic, exacting, exhausting, exhaustive, fatiguing, fervent, forced, formidable, grueling, hairy, hard-earned, hard-fought, hard-working, hardworking, heavy, hefty, indefatigable, industrious, intricate, jawbreaking, killing, knotted, knotty, labored, mean, never idle, no picnic, not easy, obdurate, obstinate, onerous, operose, oppressive, overworked, painful, painstaking, persevering, persistent, ponderous, punishing, relentless, rigorous, rough, rugged, scrupulous, sedulous, set with thorns, severe, sleepless, spiny, steadfast, steady, steep, stiff, strained, strenuous, stubborn, taxing, thorny, thorough, ticklish, tireless, toilsome, tough, tricky, troublesome, unflagging, unrelenting, unremitting, unsleeping, unsparing, untiring, unwavering, unwearied, uphill, vehement, wearisome, wearying, wicked, zealous