What does de lagrange mean in french?

"De Lagrange" in French doesn't have a specific meaning on its own. It's a surname, like "Smith" in English. It's likely you're thinking of someone named Lagrange, such as:

* Joseph-Louis Lagrange (1736-1813): A famous Italian-French mathematician and astronomer.

Without context, it's impossible to say for sure what "de Lagrange" means. If you can provide more information, I might be able to help.