diff --git a/source b/source
index 877761a9424..f6904cb08c8 100644
--- a/source
+++ b/source
@@ -56161,13 +56161,19 @@ interface <dfn interface>HTMLSelectElement</dfn> : <span>HTMLElement</span> {
   </div>
 
   <div algorithm>
-  <p>To get the <dfn data-x="concept-select-option-list">list of options</dfn> given a
-  <code>select</code> element <var>select</var>:</p>
+  <p>The <dfn data-x="concept-select-option-list">list of options</dfn> for a
+  <code>select</code> element <var>select</var> is the result of running <span>descendant
+  <code>option</code> elements</span> given <var>select</var>.</p>
+  </div>
+
+  <div algorithm>
+  <p>To get the <dfn>descendant <code>option</code> elements</dfn> of an <span data-x="HTML
+  elements">HTML element</span> <var>element</var>:</p>
 
   <ol>
    <li><p>Let <var>options</var> be « ».</p></li>
 
-   <li><p>Let <var>node</var> be the <span>first child</span> of <var>select</var> in <span>tree
+   <li><p>Let <var>node</var> be the <span>first child</span> of <var>element</var> in <span>tree
    order</span>.</p></li>
 
    <li>
@@ -56188,14 +56194,14 @@ interface <dfn interface>HTMLSelectElement</dfn> : <span>HTMLElement</span> {
        <li><p><var>node</var> is an <code>option</code> element;</p></li>
 
        <li><p><var>node</var> is an <code>optgroup</code> element and <var>node</var> has an
-       <span>ancestor</span> <code>optgroup</code> in between itself and <var>select</var>,</p></li>
-      </ul>
+       <span>ancestor</span> <code>optgroup</code> in between itself and
+       <var>element</var>,</p></li> </ul>
 
-      <p>then set <var>node</var> to the next <span>descendant</span> of <var>select</var> in
+      <p>then set <var>node</var> to the next <span>descendant</span> of <var>element</var> in
       <span>tree order</span>, excluding <var>node</var>'s <span
       data-x="descendant">descendants</span>, if any such node exists; otherwise null.</p>
 
-      <p>Otherwise, set <var>node</var> to the next <span>descendant</span> of <var>select</var> in
+      <p>Otherwise, set <var>node</var> to the next <span>descendant</span> of <var>element</var> in
       <span>tree order</span>, if any such node exists; otherwise null.</p>
      </li>
     </ol>
@@ -56825,12 +56831,13 @@ interface <dfn interface>HTMLOptGroupElement</dfn> : <span>HTMLElement</span> {
    <dd w-dev>Uses <code>HTMLOptGroupElement</code>.</dd>
   </dl>
 
-  <p>The <code>optgroup</code> element <span>represents</span> a group of <code>option</code>
-  elements with a common label.</p>
+  <p>The <code>optgroup</code> element <span>represents</span> a <span data-x="optgroup's group of
+  option elements">group of <code>option</code> elements</span> with a common label.</p>
 
   <div algorithm>
-  <p>The element's group of <code>option</code> elements consists of the <code>option</code>
-  elements that are children of the <code>optgroup</code> element.</p>
+  <p>An <dfn><code>optgroup</code>'s group of <code>option</code> elements</dfn>, given an
+  <code>optgroup</code> element <var>optgroup</var>, is the result of running <span>descendant
+  <code>option</code> elements</span> given <var>optgroup</var>.</p>
   </div>
 
   <div w-nodev>
@@ -56843,8 +56850,8 @@ interface <dfn interface>HTMLOptGroupElement</dfn> : <span>HTMLElement</span> {
 
   <p>The <dfn element-attr for="optgroup"><code
   data-x="attr-optgroup-disabled">disabled</code></dfn> attribute is a <span>boolean
-  attribute</span> and can be used to <span data-x="concept-option-disabled">disable</span> a group
-  of <code>option</code> elements together.</p>
+  attribute</span> and can be used to <span data-x="concept-option-disabled">disable</span> an
+  <span><code>optgroup</code>'s group of <code>option</code> elements</span> together.</p>
 
   <p>The <dfn element-attr for="optgroup"><code data-x="attr-optgroup-label">label</code></dfn>
   attribute must be specified if the <code>optgroup</code> has no child <code>legend</code>