pessary n.

c. 1400, pessarie, "a suppository; a medicated plug inserted into an orifice of the body," from Late Latin pessarium, from Greek pessarion "medicated tampon of wool or lint," diminutive of pessos "pessary," earlier "oval stone used in games," a word of uncertain, perhaps Semitic, origin. As an instrument worn in the vagina to remedy various uterine displacements, by 1754.