Upsilon (uppercase Υ, lowercase υ) is the 20th letter of the
Greek alphabet. In the system of
Greek numerals it has a value of 400. It is derived from the
Phoenician waw. In early Greek it was pronounced like "euw" u or English oo,
IPA . In
Classical Greek, it was pronounced like French u or German ü, IPA —a sound that is not found in most dialects of
English. In
Modern Greek it is pronounced like continental i or English ee, IPA , and in diphthongs, or . In ancient Greek it occurred in both long and short versions, but this distinction has been lost in Modern Greek.
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