The <dfn> Tag

The <dfn> tag stands for a definitional element and specifies a term that will be defined in the content. The closest parent element of the <dfn> tag should contain the definition/explanation of the term.

EXAMPLE

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>definitional element</title>
    <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1">
</head>
<body>
<p>Welcome to the <dfn title="HyperText Markup Language">HTML</dfn> tutorial!</p>
</body>
</html>

RESULT