Middle English word beswinken comes from English besmirch, English swink, Old English swincan (To toil, labour.)

Detailed word origin of beswinken

Dictionary entry	Language	Definition
besmirch	English (eng)	(transitive) To tarnish something, especially someone's reputation; to debase.. (transitive, literary) To make dirty; to soil.
swink	English (eng)	(archaic, intransitive) to labour, to work hard. (archaic, transitive) To cause to toil or drudge; to tire or exhaust with labor. (archaic) toil, work, drudgery.
swincan	Old English (ang)	To toil, labour.
beswincan	Old English (ang)	To labour for or at, swink, toil, make with toil.
beswinken	Middle English (enm)

Words with the same origin as beswinken