diff --git a/core/modules/block/block.module b/core/modules/block/block.module
index 9d5f406..8602e2a 100644
--- a/core/modules/block/block.module
+++ b/core/modules/block/block.module
@@ -238,12 +238,12 @@ function template_preprocess_block(&$variables) {
   $variables['plugin_id'] = $variables['elements']['#plugin_id'];
   $variables['base_plugin_id'] = $variables['elements']['#base_plugin_id'];
   $variables['derivative_plugin_id'] = $variables['elements']['#derivative_plugin_id'];
-  $variables['label'] = !empty($variables['configuration']['label_display']) ? $variables['configuration']['label'] : '';
+  $variables['title'] = !empty($variables['configuration']['label_display']) ? $variables['configuration']['label'] : '';
   $variables['content'] = $variables['elements']['content'];
-  // A block's label is configuration: it is static. Allow dynamic labels to be
+  // A block's title is configuration: it is static. Allow dynamic titles to be
   // set in the render array.
   if (isset($variables['elements']['content']['#title']) && !empty($variables['configuration']['label_display'])) {
-    $variables['label'] = $variables['elements']['content']['#title'];
+    $variables['title'] = $variables['elements']['content']['#title'];
   }
 
   // Create a valid HTML ID and make sure it is unique.
@@ -252,8 +252,8 @@ function template_preprocess_block(&$variables) {
   }
 
   // Proactively add aria-describedby if possible to improve accessibility.
-  if ($variables['label'] && isset($variables['attributes']['role'])) {
-    $variables['title_attributes']['id'] = Html::getUniqueId($variables['label']);
+  if ($variables['title'] && isset($variables['attributes']['role'])) {
+    $variables['title_attributes']['id'] = Html::getUniqueId($variables['title']);
     $variables['attributes']['aria-describedby'] = $variables['title_attributes']['id'];
   }
 
diff --git a/core/modules/block/templates/block.html.twig b/core/modules/block/templates/block.html.twig
index 236b3cf..ce03995 100644
--- a/core/modules/block/templates/block.html.twig
+++ b/core/modules/block/templates/block.html.twig
@@ -5,7 +5,8 @@
  *
  * Available variables:
  * - plugin_id: The ID of the block implementation.
- * - label: The configured label of the block if visible.
+ * - title: The configured title (equivalent to 'label' in internal block speak)
+ *   of the block if visible.
  * - configuration: A list of the block's configuration values.
  *   - label: The configured label for the block.
  *   - label_display: The display settings for the label.
@@ -36,8 +37,8 @@
 #}
 <div{{ attributes }}>
   {{ title_prefix }}
-  {% if label %}
-    <h2{{ title_attributes }}>{{ label }}</h2>
+  {% if title %}
+    <h2{{ title_attributes }}>{{ title }}</h2>
   {% endif %}
   {{ title_suffix }}
   {% block content %}
diff --git a/core/themes/bartik/templates/block.html.twig b/core/themes/bartik/templates/block.html.twig
index 31a95c0..674d0e6 100644
--- a/core/themes/bartik/templates/block.html.twig
+++ b/core/themes/bartik/templates/block.html.twig
@@ -5,7 +5,8 @@
  *
  * Available variables:
  * - plugin_id: The ID of the block implementation.
- * - label: The configured label of the block if visible.
+ * - title: The configured title (equivalent to 'label' in internal block speak)
+ *   of the block if visible.
  * - configuration: A list of the block's configuration values.
  *   - label: The configured label for the block.
  *   - label_display: The display settings for the label.
@@ -44,8 +45,8 @@
 %}
 <div{{ attributes.addClass(classes) }}>
   {{ title_prefix }}
-  {% if label %}
-    <h2{{ title_attributes }}>{{ label }}</h2>
+  {% if title %}
+    <h2{{ title_attributes }}>{{ title }}</h2>
   {% endif %}
   {{ title_suffix }}
   {% block content %}
diff --git a/core/themes/classy/templates/block/block--search-form-block.html.twig b/core/themes/classy/templates/block/block--search-form-block.html.twig
index 0b162dd..603bedd 100644
--- a/core/themes/classy/templates/block/block--search-form-block.html.twig
+++ b/core/themes/classy/templates/block/block--search-form-block.html.twig
@@ -5,7 +5,8 @@
  *
  * Available variables:
  * - plugin_id: The ID of the block implementation.
- * - label: The configured label of the block if visible.
+ * - title: The configured title (equivalent to 'label' in internal block speak)
+ *   of the block if visible.
  * - configuration: A list of the block's configuration values, including:
  *   - label: The configured label for the block.
  *   - label_display: The display settings for the label.
@@ -42,8 +43,8 @@
 %}
 <div{{ attributes.addClass(classes) }}>
   {{ title_prefix }}
-  {% if label %}
-    <h2{{ title_attributes }}>{{ label }}</h2>
+  {% if title %}
+    <h2{{ title_attributes }}>{{ title }}</h2>
   {% endif %}
   {{ title_suffix }}
   {% block content %}
diff --git a/core/themes/classy/templates/block/block--system-menu-block.html.twig b/core/themes/classy/templates/block/block--system-menu-block.html.twig
index 6d5371c..fc9b74f 100644
--- a/core/themes/classy/templates/block/block--system-menu-block.html.twig
+++ b/core/themes/classy/templates/block/block--system-menu-block.html.twig
@@ -5,7 +5,8 @@
  *
  * Available variables:
  * - plugin_id: The ID of the block implementation.
- * - label: The configured label of the block if visible.
+ * - title: The configured title (equivalent to 'label' in internal block speak)
+ *   of the block if visible.
  * - configuration: A list of the block's configuration values.
  *   - label: The configured label for the block.
  *   - label_display: The display settings for the label.
diff --git a/core/themes/classy/templates/block/block.html.twig b/core/themes/classy/templates/block/block.html.twig
index a85c82c..3f7527a 100644
--- a/core/themes/classy/templates/block/block.html.twig
+++ b/core/themes/classy/templates/block/block.html.twig
@@ -5,7 +5,8 @@
  *
  * Available variables:
  * - plugin_id: The ID of the block implementation.
- * - label: The configured label of the block if visible.
+ * - title: The configured title (equivalent to 'label' in internal block speak)
+ *   of the block if visible.
  * - configuration: A list of the block's configuration values.
  *   - label: The configured label for the block.
  *   - label_display: The display settings for the label.
@@ -40,8 +41,8 @@
 %}
 <div{{ attributes.addClass(classes) }}>
   {{ title_prefix }}
-  {% if label %}
-    <h2{{ title_attributes }}>{{ label }}</h2>
+  {% if title %}
+    <h2{{ title_attributes }}>{{ title }}</h2>
   {% endif %}
   {{ title_suffix }}
   {% block content %}