See also phi 496.
[1] For Phthia as the home of Achilles see Homer, Iliad 1.155-6, etc. Stephanus of Byzantium s.v. classifies it as a "city and part" of Thessaly. As the second of these things, it is (or became) more properly known as Phthiotis; as the first, it should probably be identified with its principal city, Pharsalos (so H.D. Westlake, Thessaly in the Fourth Century BC (London 1935) 11-12).
[2] Sc. land. Both (subsidiary) headword and gloss are here in the genitive case; they stem from Euripides, Andromache 861.
For at least some periods, the principal city of Phthiotis was Phthiotic Thebes.