How to exclude a file system subtree from find?

Hello,
Please, do you know how to make find exclude a file system subtree from its results?
I want to exclude a .snapshot subdirectory and all its contents but I don't know if it's possible to craft such an expression.
A crude solution could be to pipe the results through grep -v '.snapshot' but it may be not a general solution if more than one subtree share the same subdirectory name and you want just one of them.

Thanks in advance,
Carlos.