Change mid to middle

README.md

@@ -28,9 +28,10 @@ Facebook and Twitter sharing is enabled. Google Analytics is included at
 the bottom of the body, if configured. You must create favicons
 yourself.
 
-The page title is the page's title, followed by a mid dot, followed by
-the site title. If one is missing, the other is used without the mid
-dot. If both are the same, only one is used without the mid dot.
+The page title is the page's title, followed by a middle dot, followed
+by the site title. If one is missing, the other is used without the
+middle dot. If both are the same, only one is used without the middle
+dot.
 
 Every page can have a header, a body, and a footer. The header has the
 section menus, if any; the page title, if any; the page description, if