Тег <dfn></dfn>

Этот тег определяет термин.

index.html

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>New Page</title>
</head>
<body>
<p>
<dfn>ASP.NET</dfn> is an exciting web programming technology
pioneered by Microsoft that allows developers to create dynamic web pages.
</p>
</body>
</html>

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>New Page</title>
</head>
<body>
<p>
<dfn>ASP.NET</dfn> is an exciting web programming technology
pioneered by Microsoft that allows developers to create dynamic web pages.
</p>
</body>
</html>