Philaenis of Samos (in Greek, Φιλαινίς ἡ Σαμία) was supposedly the author of a famous ancient sex manual. According to a surviving fragment of her treatise, she was from Samos, and her father was called Ocymenes. However, many modern scholars consider "Philaenis" a pseudonym, and the manual attributed to her may have been written instead by an Athenian sophist, Polycrates. The manual attributed to her was well-known throughout classical antiquity and scholars believe that it may have influenced Ovid's Ars Amatoria, but, until the late twentieth century, it was thought to have been wholly lost. In 1972, three brief fragments of it were published, which had been previously discovered at Oxyrhynchus as part of the Oxyrhynchus Papyri. In later times, Philaenis was remembered in literature as a stereotypical tribade.
According to one of the surviving fragments of Philaenis' treatise, the work was written by "Philaenis the Samian, daughter of Ocymenes" – though Athenaeus calls her "Leucadian". Her mother's name is sometimes given as Gyllina. She was supposedly a courtesan, and Philaenis – a diminutive of "philaina", the feminine form of the Greek word "philos", meaning "love" – seems to have been a name commonly used by prostitutes in ancient Greece. Her association with Samos is also appropriate for a supposed prostitute; in antiquity, the island was famous for its expensive hetairai.
Two poems in the Palatine Anthology – one by Aeschrion of Samos, the other by the third-century BC poet Dioscorides – deny that Philaenis wrote the work attributed to her. Aeschrion instead attributes the work to Polycrates – most probably the Athenian sophist by that name, though this is not certain. Modern scholars generally believe that Philaenis is a pseudonym for the true author of the work, and Tsantsanolou agrees with Aeschrion's attribution of the work to Polycrates, arguing that it is consistent with what is known of his style.