In Greek mythology, Lycaon (/laɪˈkeɪɒn/; Greek: ) was a king of Arcadia, son of Pelasgus and Meliboea, who, in the most popular version of the myth, tested Zeus by serving him the roasted flesh of Lycaon's own son Nyctimus, in order to see whether Zeus was truly omniscient. In return for these gruesome deeds, Zeus transformed Lycaon and his offspring into the forms of a wolf; Nyctimus was restored to life.
Despite being notorious for his horrific deeds, Lycaon was also remembered as a culture hero: he was believed to have founded the city Lycosura, to have established a cult of Zeus Lycaeus and to have started the tradition of the Lycaean Games, which Pausanias thinks were older than the Panathenaic Games. According to Hyginus, Lycaon dedicated the first temple to Hermes of Cyllene. The Arcadian town Nonakris was thought to have been named after the wife of Lycaon.
There are several versions of the Lycaon myth already reported by Hesiod (Fragmenta astronomica, by Eratosthenes, Catasterismi), told by several authors. The most popular version is the one reported by Ovid in the first book of his Metamorphoses.
The different versions of the myth are as follows:
According to the Bibliotheca (Pseudo-Apollodorus), the 50 sons of Lycaon were:
Maenalus was in early modern times represented by the now obsolete constellation Mons Maenalus in the southern part of Boötes.