To rename a table, navigate to your table, then go to Develop > Manage Tables > Find your Table in the list.
Below the name field, there is a link "rename table". Click on it. Choose a new name for your table and click save.
Caution: Default sub-menus will be renamed to the name of the new table
Rarely, but sometimes, renaming tables can be problematic if you have other tables or data in your application that refers to the table you want to rename.