onanism
Onanism (noun) means the act of masturbating.
Etymology
Formed from Onan and -ism. In the Book of Genesis, Onan, son of Judah, was required by the laws of levirate marriage to impregnate his brother Er's widow, Tamar, so as to raise offspring in his brother's name. To avoid giving his late brother descendants, however, Onan "spilled his semen on the ground when he went in to his brother's wife, so that he would not give offspring to his brother" (Genesis 38:9).