What is the meaning of Wy?

The name of the letter Y.

obsolete form of ons

you

A letter of the Mfumte alphabet.

plural second person pronoun; you

polite singular second person pronoun; you

us

plural second person pronoun; you

polite singular second person pronoun; you

second-person plural pronoun; you

alternative form of w, used mostly before words that begin with consonant clusters

you (second-person plural)

egg

we (first-person plural nominative pronoun)

Source: wiktionary.org