Onan, \ˈō-nən\ Biblical character. In the Book of Genesis Onan was commanded by his father to impregnate the widow of his slain brother and to raise the offspring of the union. In order to avoid raising descendants for his late brother, however, Onan engaged in coitus interruptus.
Medical Dictionary
onanism
noun onan·ism \ˈō-nə-ˌniz-əm\
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