This element can be used in several very different contexts, which determine its exact meaning and usage:
As one of the semantic tags within a <term-display> element, the <def> element contains the definition for the term being described (<term>).
As the second half of a definition list item (<def-item>), which is one item in a two-part list (<def-list>), the <def> element contains a definition, description, or other explanation of the word, phrase, or picture that is the first part of each list item (<term>).
The <def> element can also be a definition or expansion of an abbreviation or acronym <abbrev>.
Any one of:
One or more of any of:
Standards Note and Example Elements