<dt> and <dd> elements must be contained by a <dl>

Description lists follow a specific structural hierarchy in HTML. The <dl> element defines the list, and within it, <dt> elements represent terms while <dd> elements provide their corresponding descriptions. When <dt> or <dd> elements exist outside of a <dl>, the browser has no context to establish the relationship between terms and definitions. This makes the content semantically meaningless to assistive technologies.

Screen reader users are most affected by this issue. Screen readers announce description lists with specific cues — for example, telling users they’ve entered a list, how many items it contains, and the relationship between terms and descriptions. When <dt> and <dd> elements lack a <dl> parent, these announcements don’t occur, and users who are blind or deafblind lose important structural context. Keyboard-only users and users with mobility impairments who rely on assistive technologies are also affected, as their tools may not properly navigate orphaned list items.

This rule relates to WCAG 2.0, 2.1, and 2.2 Success Criterion 1.3.1: Info and Relationships (Level A), which requires that information, structure, and relationships conveyed through presentation can be programmatically determined. A description list’s structure conveys a meaningful relationship between terms and definitions, so the proper HTML hierarchy must be in place for that relationship to be communicated to all users.

How to fix it

1. Wrap orphaned <dt> and <dd> elements inside a <dl> parent element.
2. Ensure proper ordering — <dt> elements should come before their associated <dd> elements.
3. Only place <dt> and <dd> elements (or <div> elements that group <dt>/<dd> pairs) as direct children of <dl>.
4. Each <dt> should have at least one corresponding <dd>, and vice versa, to form a complete term-description pair.

Examples

Incorrect: <dt> and <dd> without a <dl> parent

<dt>Coffee</dt>
<dd>A hot, caffeinated beverage</dd>
<dt>Milk</dt>
<dd>A cold, dairy-based drink</dd>

This is invalid because the <dt> and <dd> elements are not wrapped in a <dl>. Screen readers will not recognize these as a description list, and users will miss the term-definition relationships.

Correct: <dt> and <dd> wrapped in a <dl>

<dl>
  <dt>Coffee</dt>
  <dd>A hot, caffeinated beverage</dd>
  <dt>Milk</dt>
  <dd>A cold, dairy-based drink</dd>
</dl>

Correct: using <div> to group term-description pairs inside <dl>

HTML allows <div> elements as direct children of <dl> to group each <dt>/<dd> pair, which can be useful for styling:

<dl>
  <div>
    <dt>Coffee</dt>
    <dd>A hot, caffeinated beverage</dd>
  </div>
  <div>
    <dt>Milk</dt>
    <dd>A cold, dairy-based drink</dd>
  </div>
</dl>

Incorrect: <dd> nested inside an unrelated element

<div>
  <dd>This description has no list context</dd>
</div>

A <dd> inside a <div> (or any non-<dl> parent) is invalid. Replace the <div> with a <dl> and add a corresponding <dt>:

<dl>
  <dt>Term</dt>
  <dd>This description now has proper list context</dd>
</dl>

Learn more:

Deque Reference

Deque University - How To Fix

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W3C Reference

WCAG 2.1 - Using description lists

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W3C Reference

WCAG 2.1 - Using ol, ul and dl for lists

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