Cuckold historically referred to a man with an adulterous wife. It has largely fallen out of use in modern English with the decline of marital infidelity in pop culture literature. In modern English it generally refers to the sexual fetish of the same name in which a male gains sexual gratification from his partner's having sex with other males.
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It´snot bad, it´s just sharing your wife whit bull´s (her favorite bull). Try it...