I’m not going to ask what you are referring to, but perhaps these are words that only allude to things that we don’t talk about and are not words for those things themselves. Much like we have in Aramaic and Loshon Kodesh.
Also, until I can find a mekor for this idea I can’t really argue whether Yeshivish is a language or not. I was just giving over what I have heard. But I will ask around and see if I can come up with something.