tighter - fixes #223

spec.html

@@ -1441,7 +1441,7 @@ <h4>Operator, Fence, Separator or Accent <code>&lt;mo&gt;</code></h4>
             <p>
               In the following example, the [^mo^] element
               is used for the binary operator +. Default spacing is symmetric
-              around that operator. A tigher spacing is used if you rely
+              around that operator. A tighter spacing is used if you rely
               on the <a><code>form</code></a> attribute to force it to be
               treated as a prefix operator.
               Spacing can also be specified explicitly using the