What is "polydamna"

Polydamna (Πολύδαμνα) is a figure from Greek mythology.

Mentioned in Homer’s Odyssey, she is the wife of Thōn (Θῶν, gen: Θῶνος). They are both Egyptians. Polydamna gave Helen, wife of Menelaus, nepenthe i.e. a drug that has “the power of robbing grief and anger of their sting and banishing all painful memories” and which Helen slipped into the wine that Telemachus and Menelaus were drinking.