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Upsilon
Twentieth letter in the Greek alphabet / From Wikipedia, the free encyclopedia
Not to be confused with Epsilon.
This article is about the Greek upsilon. For the Latin upsilon, see ʊ. For other uses, see Upsilon (disambiguation).
"Ypsilon" redirects here. For other uses, see Ypsilon (disambiguation).
Upsilon (US: /ˈʌpsɪˌlɒn, ˈ(j)uːp-, -lən/, UK: /(j)uːpˈsaɪlən, ʊp-, -lɒn/;[1][2][3][4][5][6] uppercase Υ, lowercase υ; Greek: ύψιλον ýpsilon [ˈipsilon]) or ypsilon /ɪp-/[1] is the twentieth letter of the Greek alphabet. In the system of Greek numerals, Υʹ has a value of 400. It is derived from the Phoenician waw .
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