From Σουσαννα (Sousanna), the Greek form of the Hebrew name שׁוֹשַׁנָּה (Shoshannah). This was derived from the Hebrew word שׁוֹשָׁן (shoshan) meaning "lily" (in modern Hebrew this also means "rose"), perhaps ultimately from Egyptian sšn "lotus". In the Old Testament Apocrypha this is the name of a woman falsely accused of adultery. The prophet Daniel clears her name by tricking her accusers, who end up being condemned themselves. It also occurs in the New Testament belonging to a woman who ministers to Jesus.
As an English name, it was occasionally used during the Middle Ages in honour of the Old Testament heroine. It did not become common until after the Protestant Reformation, at which time it was often spelled Susan.