<overline>
  
  
  An overline is a horizontal line that is printed above a line of text, a mathematical symbol, or an illustration in a newspaper or journal.
Rendering expectations
The content of the <overline> element is
        typically rendered with a line above it.
Specialization hierarchy
The <overline> element is specialized from
          <ph>. It is defined in the highlighting-domain module.
Content model
(Text | <cite> | <include> | <keyword> | <ph> | <q> | <term> | <text> | <tm> | <xref> | <data> | <draft-comment> | <foreign> | <required-cleanup>)*
Not contained by any element.
Not contained by any element.
Inheritance
+ topic/ph hi-d/overline
The <overline> element is specialized from <ph>. It is defined in the hi-domain module.
Attributes
The following attributes are
        available on this element: universal
                                                  attributes and @keyref.
The following attributes are available on this element: universal attributes and the attributes defined below.
- @keyref
- Specifies a key name that acts as a redirectable reference based on a key definition within a map. See The keyref attribute for information on using this attribute.
Example
This section is non-normative.
The following code sample shows an <overline
        > element used to provide the highlighting used for
        mathematical notation:
<p>Overline: <overline><i>x</i></overline> is the 
average value of<i>x<sub>i</sub></i></p>