Here are some possible interpretations:
* A misspelling of "Grec": This is the French word for "Greek".
* A regional dialect word: There could be a specific dialect or region where "grégeois" is used, but it's not widely known.
* A made-up word: It's possible the word is entirely fabricated.
If you can provide more context, such as where you encountered this word, I might be able to help you better understand its meaning.