Y

Y (named wye/ˈwaɪ/, plural wyes) is the 25th and penultimate letter in the modern English alphabet and the ISO basic Latin alphabet. In the English writing system, it sometimes represents a vowel and sometimes a consonant.

In Latin, Y was named I graeca, since the classical Greek sound /y/, similar to modern German ü or French u, was not a native sound for Latin speakers, and the letter was initially only used to spell foreign words. This history has led to the standard modern names of the letter in Romance languages – i grego in Galician, i grega in Catalan, i grec in French and Romanian, i greca in Italian – all meaning "Greek I". The names igrek in Polish and i gờ-rét in Vietnamese are both phonetic borrowings of the French name. In Dutch, both Griekse ij and i-grec are used. In Spanish, Y is also called i griega; however, in the twentieth century, the shorter name ye was proposed and was officially recognized as its name in 2010 by the Real Academia Española, although its original name is still accepted. The original Greek name υ ψιλον (upsilon) has also been adapted into several modern languages: in German, for example, it is called Ypsilon, and in Italian the name is ipsilon or i greca. In Portuguese, both names are used (ípsilon and i grego).

Old English borrowed Latin Y to write the native Old English sound /y/ (previously written with the rune yr ᚣ). The name of the letter may be related to 'ui' (or 'vi') in various medieval languages; in Middle English it was 'wi' /wiː/, which through the Great Vowel Shift became the Modern English 'wy' /waɪ/.

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