Definition of "y"

The twenty-fifth letter of the English alphabet, called wy or wye and written in the Latin script.  examples

Abbreviation of year.  quotations  examples

(UK, television) Abbreviation of youth, usually followed by an age appropriate for the content so marked.  examples

(computing) Abbreviation of yes.  examples

(slang, text messaging, Internet slang, stenoscript) Abbreviation of why.