     |
<element name="element-name">
<ref name="element-content"/>
</element>
<define name="element-content">
<attribute name="attribute1">
<text/>
</attribute>
<attribute name="attribute2">
<text/>
</attribute>
</define>
The define element allows to specify a name for a pattern.
The ref element references a defined pattern by name.
Define elements can only be specified as a child of the top 'grammar' element.