The only such language I can think of now is Excel. It has different function names in different language versions.
Some submissions can be made shorter by changing the language from the language default on this site, namely English.
This may also be used in obfuscation challenges (although in my opinion you should specify the locale version you're using).
Is it fair to use the specific locale versions of the same programming language?
Note: It's not about locale-specific output (like here), but the function names being different in different locales