<dl> elements must only directly contain properly-ordered <dt> and <dd> groups, <script>, or <template> elements

Rule ID: definition-list
User Impact: Serious
WCAG: 1.3.1

Compliance Data & Impact

User Impact

Disabilities Affected

  • Blind
  • Deafblind


  • WCAG 2.0 (A): MUST

WCAG Success Criteria

  • 1.3.1 Info and Relationships

Section 508 Guidelines

  • Not specified, or not applicable

Rule Description

Definition lists (dl) must contain only properly-ordered dt and dd groups, script or template elements.

Why it Matters

Screen readers have a specific way of announcing definition lists. When such lists are not properly marked up, this creates the opportunity for confusing or inaccurate screen reader output.

A definition list is used to provide the definitions of words or phrases. The Definition List is marked up using the dl element. Within the list, each term is put in a separate dt element, and its definition goes in the dd element directly following it.

How to Fix the Problem

Check that your definition list has only dt and dd elements. Furthermore, make sure these are properly ordered, dt should precede dd elements.

Definition list items require dl elements around the list, dt elements for each term, and dd elements for each definition. Each set of dt elements must be followed by one or more dd elements. Ensure that your definition lists follow these specifications and mimic the example below.


  <dd>Black hot drink</dd>
  <dd>White cold drink</dd>

The Algorithm (in simple terms)

Ensures that all dl elements are structured correctly.