moil \MOYL\ (intransitive verb) - 1 : To work with painful effort; to labor; to toil; to drudge. 2 : To churn or swirl about continuously.
(noun) - 1 : Toil; hard work; drudgery. 2 : Confusion; turmoil.
"Moil and toil, moil and toil, from morning to night, and no thanks whatever." -- George Manville Fenn, 'Nat the Naturalist'
Moil comes from Middle English moillen, "to soak, to wet," hence "to soil, to soil one's hands, to work very hard," from Old French moillier, "to soften, especially by making wet," ultimately from Latin mollis, "soft."