Add a definition

I was not sure if it understands the difference between an HTML element and a HTML tag.

Also not directly related to the abbr issue.

scripts/translate.py

@@ -108,6 +108,9 @@ The above rules are in effect now.
         ```
         »»»
 
+"HTML element"
+
+    a HTML opening tag – e.g. «<div>» – and a HTML closing tag – e.g. «</div>» – wrapping text or other HTML elements.
 
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