Upsilon

Upsilon (US: /ˈʌpsɪˌlɒn, ˈ(j)p-, -lən/, UK: /(j)pˈslən, 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 .

The Greek alphabet on a black figure vessel, with a V-shaped upsilon
  1. ^ a b "upsilon". Chambers Dictionary (9th ed.). Chambers. 2003. ISBN 0-550-10105-5.
  2. ^ "upsilon". Collins English Dictionary (13th ed.). HarperCollins. 2018. ISBN 978-0-008-28437-4.
  3. ^ "Upsilon". Merriam-Webster.com Dictionary. Merriam-Webster. Retrieved 2016-01-22.
  4. ^ "Upsilon". Lexico UK English Dictionary. Oxford University Press. Archived from the original on 2019-12-21.
  5. ^ "upsilon". Dictionary.com Unabridged (Online). n.d. Retrieved 2016-01-22.
  6. ^ "upsilon". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)