diff -u b/core/modules/breakpoint/breakpoint.module b/core/modules/breakpoint/breakpoint.module
--- b/core/modules/breakpoint/breakpoint.module
+++ b/core/modules/breakpoint/breakpoint.module
@@ -82,7 +82,7 @@
  * Import media queries from a theme or module and create a default group.
  *
  * @param string $id
- *   Name of the breakpoint group.
+ *   Identifier of the breakpoint group.
  * @param string $label
  *   Human readable name of the breakpoint group.
  * @param string $sourceType
@@ -156,14 +156,14 @@
       $breakpoint_group->delete();
 
       // Get all breakpoints defined by this theme/module.
-      $names = drupal_container()->get('config.storage')->listAll('breakpoint.breakpoint.' . $source_type . '.' . $breakpoint_group->id() . '.');
+      $breakpoint_ids = drupal_container()->get('config.storage')->listAll('breakpoint.breakpoint.' . $source_type . '.' . $breakpoint_group->id() . '.');
       $entity_info = entity_get_info('breakpoint');
 
-      // Remove the breakpoint.breakpoint part of the names, before loading.
-      foreach ($names as &$name) {
-        $name = drupal_substr($name, drupal_strlen($entity_info['config prefix']) + 1);
+      // Remove the breakpoint.breakpoint part of the breakpoint identifier.
+      foreach ($breakpoint_ids as &$breakpoint_id) {
+        $breakpoint_id = drupal_substr($breakpoint_id, drupal_strlen($entity_info['config prefix']) + 1);
       }
-      $breakpoints = entity_load_multiple('breakpoint', $names);
+      $breakpoints = entity_load_multiple('breakpoint', $breakpoint_ids);
 
       // Make sure we only delete breakpoints defined by this theme/module.
       foreach ($breakpoints as $breakpoint) {
diff -u b/core/modules/breakpoint/lib/Drupal/breakpoint/BreakpointGroup.php b/core/modules/breakpoint/lib/Drupal/breakpoint/BreakpointGroup.php
--- b/core/modules/breakpoint/lib/Drupal/breakpoint/BreakpointGroup.php
+++ b/core/modules/breakpoint/lib/Drupal/breakpoint/BreakpointGroup.php
@@ -17,7 +17,7 @@
 class BreakpointGroup extends ConfigEntityBase {
 
   /**
-   * The breakpoint group ID (machine name).
+   * The breakpoint group ID.
    *
    * @var string
    */
@@ -257,11 +257,11 @@
    * Import breakpoint groups from theme or module.
    *
    * @param string $source
-   *   Source of the breakpoint group, theme_key or module name.
+   *   Source of the breakpoint group: theme_key or module name.
    * @param string $sourceType
    *   Either Breakpoint::SOURCE_TYPE_THEME or Breakpoint::SOURCE_TYPE_MODULE.
-   * @param string $name
-   *   Name of the breakpoint group.
+   * @param string $id
+   *   Identifier of the breakpoint group.
    * @param string $label
    *   Human readable name of the breakpoint group.
    * @param array $breakpoints
@@ -270,20 +270,20 @@
    * @return \Drupal\breakpoint\BreakpointGroup|false
    *   Return the new breakpoint group containing all breakpoints.
    */
-  public static function ImportBreakpointGroup($source, $source_type, $name, $label, $breakpoints) {
+  public static function ImportBreakpointGroup($source, $source_type, $id, $label, $breakpoints) {
     // Use the existing breakpoint group if it exists.
-    $breakpoint_group = entity_load('breakpoint_group', $source_type . '.' . $name);
+    $breakpoint_group = entity_load('breakpoint_group', $source_type . '.' . $id);
     if (!$breakpoint_group) {
       $breakpoint_group = entity_create('breakpoint_group', array(
-        'id' => $name,
-        'label' => !empty($label) ? $label : $name,
+        'id' => $id,
+        'label' => !empty($label) ? $label : $id,
         'source' => $source,
         'sourceType' => $source_type,
       ));
     }
     else {
       // Reset label.
-      $breakpoint_group->label = !empty($label) ? $label : $name;
+      $breakpoint_group->label = !empty($label) ? $label : $id;
     }
 
     // Add breakpoints to the group.