In Greek mythology, Cilix (Ancient Greek Κίλιξ) is a Phoenician prince, son of Agenor and Telephassa (or Argiope), brother of Cadmus, Phoenix, and Europa. Sent to recover Europa after Zeus carries her off, he abandons the search and settles in Asia Minor; the land and people take the name Cilicia from him.
Adapted from Wikipedia, "Cilix" · CC BY-SA 4.0
I.Brother of Europa
Apollodorus makes Cilix son of Agenor who, with Cadmus and Phoenix, is ordered never to return without Europa. The search fails; Cilix settles near Phoenicia about the Pyramus, and the country is called Cilicia after him. Herodotus knows the eponym among peoples of that coast.
Diodorus and Hyginus vary siblings and companions (Thasus as brother or nephew). Later literary retellings (e.g. Hawthorne) expand his remorse at quitting the quest; the core atlas fact remains the Agenorid eponym who founds or names Cilicia when Europa cannot be found.
II.Homonym note
Cilix is this Agenorid prince alone. Aegean or Mysian districts also called Cilicia in geography are place-names, not a second mythic brother.