upsilon
noun /ʌpˈsaɪlən/, /ˈʊpsɪlɒn/
/ˈʊpsɪlɑːn/
- the 20th letter of the Greek alphabet (ϒ, υ)
希腊字母表的第 20 个字母 词源Greek, literally ‘slender U’, from psilos ‘slender’, referring to the need to distinguish upsilon from the diphthong oi: in late Greek the two had the same pronunciation.