What is the Yiddish word for a non-Jewish boy?
Before continuing, I ask that you please remember that the Yiddish language in its written form uses the Hebrew alphabet; and that oftentimes, in its transliteration into English, there are a variety of spellings when Romanized.
Thus, when written into the English language, the Yiddish word shaygetz may also be spelled as sheigetz, shaigetz, sheygets, or shegetz.
There is an article in Wikipedia on this Yiddish word, read about it as it is entitled over there:
Please note that shegetz refers to a male not a female. Think of it this way, “Hey, (pronounced as hay) he gets what he wants.”
That is why I prefer the spelling of shaygetz over shegetz.
Now then, if you want to discuss how she gets what she wants when discussing a non-Jewish girl, take a look at shiksa (aka שיקסע, shíkseh, shikse, or schicksa).