Address @svgeesus's comment

Author: litherum

css-fonts-5/Overview.bs

@@ -192,7 +192,7 @@ descriptor value is a percentage, the corresponding metric value is resolved as
 given percentage multiplied by the used font size. Negative values are invalid at parse time.
 
 For the 'advance-override' descriptor, when the descriptor value is a percentage, the
-spacing between adjacent <a>typographic character units</a> is multiplied by the percentage.
+advance from one <a>typographic character unit</a> to the next is multiplied by the percentage.
 
 Note: Using the 'ascent-override', 'descent-override', and 'line-grap-override' descriptors can
 achieve a similar effect as specifying a percentage for 'line-height' property. Also, using the