Upsilon
/ˈʊp.sɪ.lɒn/noun
The twentieth letter of the Greek alphabet, written Υ or υ and traditionally transliterated as y or u.
Did you know?Greek grammarians called υ “bare” or “simple” because it contrasted with ου, the vowel combination representing a related rounded vowel sound.
Etymological Timeline
Classical Greek
Greek
ὖ ψιλόν (û psilón)
““Bare” or “simple u,” distinguishing υ from the diphthong ου”
Hellenistic Greek
Greek
υ ψιλόν (u psilón)
“The standalone or simple upsilon vowel”
Late Antiquity
Greek
οὖ ψιλόν / ὖ ψιλόν
“A grammatical name for the letter υ, contrasting it with compound vowel spellings”
Medieval Latin
Latin
ypsilon
“The Greek letter υ, adopted into Latin scholarly terminology”
16th Century
English
upsilon
“The name of the Greek letter υ”
Modern English
English
upsilon
“The twentieth letter of the Greek alphabet”
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