ξῖ

Forms

ξῖ (xî) n (indeclinable)^[1] The older spelling is ξεῖ (xeî), whose ⟨ει⟩ stood for a long close /eː/.^[2][3][4] The form ξῦ (xû), made on the model of νῦ (nû), is a false reading in Lucian and the Palatine Anthology.^[4][5]

Etymology

It is from Ancient Greek ξεῖ (xeî), the older spelling, rewritten with ⟨ι⟩ once ⟨ει⟩ and ⟨ι⟩ were pronounced alike.^[2][5][4] ξεῖ is a Greek formation: the letter was named on the model of πεῖ (peî), the name of π.^[2][3][6] The letter itself is the Semitic samekh, which the eastern Greek alphabets adopted to write /ks/, and Rosół compares the Hebrew and Aramaic names of that letter.^[2][6] He rejects the view, held by Jeffery and Powell among others, that the Greek name comes from the Semitic letter name shin.^[6]

Earliest recorded meaning

The letter is first named, in the spelling ξεῖ, by the comic poet Callias, quoted by Athenaeus; the spelling ξῖ appears in Lucian in the 2nd century AD.^[4][2][3]

Semantic evolution

ξεῖ is also found in an inscription from Delos and in Philodemus.^[4] Later, ξῖ is the usual spelling, for example in the scholia on Dionysius Thrax and in the musical treatises of Alypius and Gaudentius.^[4][7]

Modern Greek ξι (ksi) is a learned continuation of the ancient name.^[5] The English word xi is recorded from the early 15th century.^[8]

Timeline

• 5th century BC – The comic poet Callias names the letter in the older spelling ξεῖ (xeî).^[4][2]
• 1st century BC – Philodemus uses the same older spelling.^[4]
• 2nd century AD – Lucian has the spelling ξῖ.^[4][3]
• 3rd to 4th century AD – Alypius and Gaudentius use it in their musical treatises.^[7]
• Early 15th century – The English word xi is first recorded.^[8]

Meanings

Noun

1. Xi, the name of the letter Ξ, ξ.^[4][9]

Related words

• ξεῖ (xeî)
• πεῖ (peî)
• πῖ (pî)
• English xi

References

1. ^ a b c d Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f Chantraine, Pierre (2009), Dictionnaire étymologique de la langue grecque: histoire des mots, new ed. with a supplement (Chroniques d'étymologie grecque 1–10), Paris: Klincksieck
3. ^ a b c d Frisk, Hjalmar (1960–1972), Griechisches etymologisches Wörterbuch, 3 vols, Heidelberg: Carl Winter
4. ^ a b c d e f g h i j Liddell, Henry George; Scott, Robert; Jones, Henry Stuart (1940), A Greek-English Lexicon, 9th ed., Oxford: Clarendon Press
5. ^ a b c Ινστιτούτο Νεοελληνικών Σπουδών (Ίδρυμα Μανόλη Τριανταφυλλίδη) (1998), Λεξικό της κοινής νεοελληνικής, Thessaloniki: Aristotle University of Thessaloniki
6. ^ a b c Rosół, Rafał (2013), Frühe semitische Lehnwörter im Griechischen, Frankfurt am Main: Peter Lang
7. ^ a b Keersmaekers, Alek (2021–2025), GLAUx: The Greek Language Automated corpus, https://github.com/alekkeersmaekers/glaux
8. ^ a b Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
9. ^ Korinthios, J. (2025), Grande Dizionario Greco Classico: Greco–Italiano, digital ed., Milan: Hoepli