routing/working with message obj/dot instead of period

Author: ducin

book/routing.rst

@@ -755,7 +755,7 @@ routing system can be:
 
 As you've seen, this route will only match if the ``{culture}`` portion of
 the URL is either ``en`` or ``fr`` and if the ``{year}`` is a number. This
-route also shows how you can use a period between placeholders instead of
+route also shows how you can use a dot between placeholders instead of
 a slash. URLs matching this route might look like:
 
 * ``/articles/en/2010/my-post``