A Christian cope you'll find online, is the false belief that the word "Jew" was never in the bible and was added to replace the word "Hebrew". This is another one of those lies created to convince
the "noticer" movement that Jesus wasn't Jewish or talking about Jews.

While the letter "J" isn't a thing in Classic Latin or Greek and therefore words like "Jesus" or "Jew" didn't exist, the Romans did have a word for Jews/Judeans, it was "Iudaei", which is in the bible and used to describe Jesus.