htmlFor

label - The ID of a <a href="/en-US/docs/Web/Guide/HTML/Content_categories#Form_labelable">labelable</a> form-related element in the same document as the label element. The first such element in the document with an ID matching the value of the <code>for</code> attribute is the <em>labeled control </em>for this label element.<br>  

A label element can have both a <code>for</code> attribute and a contained control element, as long as the <code>for</code> attribute points to the contained control element. output - A list of IDs of other elements, indicating that those elements contributed input values to (or otherwise affected) the calculation.