moil
v.
"to labour in the mire" [Johnson], c.1400, from Old French moillier "to wet, moisten" (12c., Modern French mouiller), from Vulgar Latin *molliare, from Latin mollis "soft," from PIE *mel- "soft" (see mild). Related: Moiled; moiling.
n.
"toil, labor," 1612, from moil, v..