diff --git a/core/lib/Drupal/Component/Plugin/ContextAwarePluginBase.php b/core/lib/Drupal/Component/Plugin/ContextAwarePluginBase.php
index 2d499fd7dd..dadb8b4f9d 100644
--- a/core/lib/Drupal/Component/Plugin/ContextAwarePluginBase.php
+++ b/core/lib/Drupal/Component/Plugin/ContextAwarePluginBase.php
@@ -72,7 +72,7 @@ public function getContextDefinitions() {
       return $definition->getContextDefinitions();
     }
     else {
-      return !empty($definition['context']) ? $definition['context'] : [];
+      return !empty($definition['context_definitions']) ? $definition['context_definitions'] : [];
     }
   }
 
@@ -86,8 +86,8 @@ public function getContextDefinition($name) {
         return $definition->getContextDefinition($name);
       }
     }
-    elseif (!empty($definition['context'][$name])) {
-      return $definition['context'][$name];
+    elseif (!empty($definition['context_definitions'][$name])) {
+      return $definition['context_definitions'][$name];
     }
     throw new ContextException(sprintf("The %s context is not a valid context.", $name));
   }
diff --git a/core/lib/Drupal/Core/Annotation/ContextDefinition.php b/core/lib/Drupal/Core/Annotation/ContextDefinition.php
index 9e28d5a6ed..6a46c01e5a 100644
--- a/core/lib/Drupal/Core/Annotation/ContextDefinition.php
+++ b/core/lib/Drupal/Core/Annotation/ContextDefinition.php
@@ -14,14 +14,14 @@
  * interactions through providing limits, and mapping contexts to appropriate
  * plugins. Context definitions can be provided as such:
  * @code
- *   context = {
+ *   context_definitions = {
  *     "node" = @ContextDefinition("entity:node")
  *   }
  * @endcode
  *
  * To add a label to a context definition use the "label" key:
  * @code
- *   context = {
+ *   context_definitions = {
  *     "node" = @ContextDefinition("entity:node", label = @Translation("Node"))
  *   }
  * @endcode
@@ -29,7 +29,7 @@
  * Contexts are required unless otherwise specified. To make an optional
  * context use the "required" key:
  * @code
- *   context = {
+ *   context_definitions = {
  *     "node" = @ContextDefinition("entity:node", required = FALSE, label = @Translation("Node"))
  *   }
  * @endcode
@@ -37,7 +37,7 @@
  * To define multiple contexts, simply provide different key names in the
  * context array:
  * @code
- *   context = {
+ *   context_definitions = {
  *     "artist" = @ContextDefinition("entity:node", label = @Translation("Artist")),
  *     "album" = @ContextDefinition("entity:node", label = @Translation("Album"))
  *   }
@@ -45,7 +45,7 @@
  *
  * Specifying a default value for the context definition:
  * @code
- *   context = {
+ *   context_definitions = {
  *     "message" = @ContextDefinition("string",
  *       label = @Translation("Message"),
  *       default_value = @Translation("Checkout complete! Thank you for your purchase.")
diff --git a/core/lib/Drupal/Core/Block/Annotation/Block.php b/core/lib/Drupal/Core/Block/Annotation/Block.php
index 99d731d08b..cb694eb587 100644
--- a/core/lib/Drupal/Core/Block/Annotation/Block.php
+++ b/core/lib/Drupal/Core/Block/Annotation/Block.php
@@ -38,4 +38,26 @@ class Block extends Plugin {
    */
   public $category = '';
 
+  /**
+   * An array of context definitions describing the context used by the plugin.
+   *
+   * The array is keyed by context names.
+   *
+   * @var \Drupal\Core\Annotation\ContextDefinition[]
+   *
+   * @deprecated Providing context definitions via the "context" key is
+   *   deprecated in Drupal 8.7.x and will be removed before Drupal 9.0.0. Use
+   *   the "context_definitions" key instead.
+   */
+  public $context = [];
+
+  /**
+   * An array of context definitions describing the context used by the plugin.
+   *
+   * The array is keyed by context names.
+   *
+   * @var \Drupal\Core\Annotation\ContextDefinition[]
+   */
+  public $context_definitions = [];
+
 }
diff --git a/core/lib/Drupal/Core/Condition/Annotation/Condition.php b/core/lib/Drupal/Core/Condition/Annotation/Condition.php
index b6686cf6b0..66a74d34ed 100644
--- a/core/lib/Drupal/Core/Condition/Annotation/Condition.php
+++ b/core/lib/Drupal/Core/Condition/Annotation/Condition.php
@@ -54,9 +54,22 @@ class Condition extends Plugin {
    * The array is keyed by context names.
    *
    * @var \Drupal\Core\Annotation\ContextDefinition[]
+   *
+   * @deprecated Providing context definitions via the "context" key is
+   *   deprecated in Drupal 8.7.x and will be removed before Drupal 9.0.0. Use
+   *   the "context_definitions" key instead.
    */
   public $context = [];
 
+  /**
+   * An array of context definitions describing the context used by the plugin.
+   *
+   * The array is keyed by context names.
+   *
+   * @var \Drupal\Core\Annotation\ContextDefinition[]
+   */
+  public $context_definitions = [];
+
   /**
    * The category under which the condition should listed in the UI.
    *
diff --git a/core/lib/Drupal/Core/Plugin/Context/ContextHandler.php b/core/lib/Drupal/Core/Plugin/Context/ContextHandler.php
index c7517a9bdd..8967267be3 100644
--- a/core/lib/Drupal/Core/Plugin/Context/ContextHandler.php
+++ b/core/lib/Drupal/Core/Plugin/Context/ContextHandler.php
@@ -43,8 +43,8 @@ protected function getContextDefinitions($plugin_definition) {
     if ($plugin_definition instanceof ContextAwarePluginDefinitionInterface) {
       return $plugin_definition->getContextDefinitions();
     }
-    if (is_array($plugin_definition) && isset($plugin_definition['context'])) {
-      return $plugin_definition['context'];
+    if (is_array($plugin_definition) && isset($plugin_definition['context_definitions'])) {
+      return $plugin_definition['context_definitions'];
     }
     return NULL;
   }
diff --git a/core/lib/Drupal/Core/Plugin/DefaultPluginManager.php b/core/lib/Drupal/Core/Plugin/DefaultPluginManager.php
index c74fcbe958..a9a157a5d1 100644
--- a/core/lib/Drupal/Core/Plugin/DefaultPluginManager.php
+++ b/core/lib/Drupal/Core/Plugin/DefaultPluginManager.php
@@ -3,6 +3,7 @@
 namespace Drupal\Core\Plugin;
 
 use Drupal\Component\Assertion\Inspector;
+use Drupal\Component\Plugin\ContextAwarePluginInterface as ComponentContextAwarePluginInterface;
 use Drupal\Component\Plugin\Definition\PluginDefinitionInterface;
 use Drupal\Component\Plugin\Discovery\CachedDiscoveryInterface;
 use Drupal\Core\Cache\CacheableDependencyInterface;
@@ -286,6 +287,7 @@ protected function findDefinitions() {
       $this->processDefinition($definition, $plugin_id);
     }
     $this->alterDefinitions($definitions);
+    $this->fixContextAwareDefinitions($definitions);
     // If this plugin was provided by a module that does not exist, remove the
     // plugin definition.
     foreach ($definitions as $plugin_id => $plugin_definition) {
@@ -297,6 +299,38 @@ protected function findDefinitions() {
     return $definitions;
   }
 
+  /**
+   * Fix the definitions of context-aware plugins.
+   *
+   * @param array $definitions
+   *   The array of plugin definitions.
+   *
+   * @todo Remove before Drupal 9.0.0.
+   */
+  private function fixContextAwareDefinitions(array &$definitions) {
+    foreach ($definitions as $name => &$definition) {
+      if (is_array($definition) && is_subclass_of($definition['class'], ComponentContextAwarePluginInterface::class) && (!empty($definition['context']) || !empty($definition['context_definitions']))) {
+        // Ensure the new definition key is available.
+        if (!isset($definition['context_definitions'])) {
+          $definition['context_definitions'] = [];
+        }
+
+        // If a context definition is defined with the old key, add it to the
+        // new key and trigger a deprecation error.
+        if (!empty($definition['context'])) {
+          $definition['context_definitions'] += $definition['context'];
+          @trigger_error('Providing context definitions via the "context" key is deprecated in Drupal 8.7.x and will be removed before Drupal 9.0.0. Use the "context_definitions" key instead.', E_USER_DEPRECATED);
+        }
+
+        // Copy the context definitions from the new key to the old key for
+        // backwards compatibility.
+        if (isset($definition['context'])) {
+          $definition['context'] = $definition['context_definitions'];
+        }
+      }
+    }
+  }
+
   /**
    * Extracts the provider from a plugin definition.
    *
diff --git a/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestContextAwareBlock.php b/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestContextAwareBlock.php
index e5017f5448..178643c2ec 100644
--- a/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestContextAwareBlock.php
+++ b/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestContextAwareBlock.php
@@ -12,7 +12,7 @@
  * @Block(
  *   id = "test_context_aware",
  *   admin_label = @Translation("Test context-aware block"),
- *   context = {
+ *   context_definitions = {
  *     "user" = @ContextDefinition("entity:user", required = FALSE)
  *   }
  * )
diff --git a/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestContextAwareUnsatisfiedBlock.php b/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestContextAwareUnsatisfiedBlock.php
index f70e8e2e6e..d0789e37a7 100644
--- a/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestContextAwareUnsatisfiedBlock.php
+++ b/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestContextAwareUnsatisfiedBlock.php
@@ -10,7 +10,7 @@
  * @Block(
  *   id = "test_context_aware_unsatisfied",
  *   admin_label = @Translation("Test context-aware unsatisfied block"),
- *   context = {
+ *   context_definitions = {
  *     "user" = @ContextDefinition("entity:foobar")
  *   }
  * )
diff --git a/core/modules/language/src/Plugin/Condition/Language.php b/core/modules/language/src/Plugin/Condition/Language.php
index 52a89a2d0f..bbbce83745 100644
--- a/core/modules/language/src/Plugin/Condition/Language.php
+++ b/core/modules/language/src/Plugin/Condition/Language.php
@@ -15,7 +15,7 @@
  * @Condition(
  *   id = "language",
  *   label = @Translation("Language"),
- *   context = {
+ *   context_definitions = {
  *     "language" = @ContextDefinition("language", label = @Translation("Language"))
  *   }
  * )
diff --git a/core/modules/layout_builder/src/Plugin/Derivative/ExtraFieldBlockDeriver.php b/core/modules/layout_builder/src/Plugin/Derivative/ExtraFieldBlockDeriver.php
index d6621c0f47..1a6bb6699b 100644
--- a/core/modules/layout_builder/src/Plugin/Derivative/ExtraFieldBlockDeriver.php
+++ b/core/modules/layout_builder/src/Plugin/Derivative/ExtraFieldBlockDeriver.php
@@ -100,7 +100,7 @@ public function getDerivativeDefinitions($base_plugin_definition) {
 
           $context_definition = EntityContextDefinition::fromEntityType($entity_type)
             ->addConstraint('Bundle', [$bundle_id]);
-          $derivative['context'] = [
+          $derivative['context_definitions'] = [
             'entity' => $context_definition,
           ];
 
diff --git a/core/modules/layout_builder/src/Plugin/Derivative/FieldBlockDeriver.php b/core/modules/layout_builder/src/Plugin/Derivative/FieldBlockDeriver.php
index 57d2c1ec7c..ae6771b118 100644
--- a/core/modules/layout_builder/src/Plugin/Derivative/FieldBlockDeriver.php
+++ b/core/modules/layout_builder/src/Plugin/Derivative/FieldBlockDeriver.php
@@ -120,7 +120,7 @@ public function getDerivativeDefinitions($base_plugin_definition) {
 
           $context_definition = EntityContextDefinition::fromEntityTypeId($entity_type_id)->setLabel($entity_type_labels[$entity_type_id]);
           $context_definition->addConstraint('Bundle', [$bundle]);
-          $derivative['context'] = [
+          $derivative['context_definitions'] = [
             'entity' => $context_definition,
           ];
 
diff --git a/core/modules/node/src/Plugin/Condition/NodeType.php b/core/modules/node/src/Plugin/Condition/NodeType.php
index dcd2dc7d30..93e18c09ae 100644
--- a/core/modules/node/src/Plugin/Condition/NodeType.php
+++ b/core/modules/node/src/Plugin/Condition/NodeType.php
@@ -14,7 +14,7 @@
  * @Condition(
  *   id = "node_type",
  *   label = @Translation("Node Bundle"),
- *   context = {
+ *   context_definitions = {
  *     "node" = @ContextDefinition("entity:node", label = @Translation("Node"))
  *   }
  * )
diff --git a/core/modules/system/tests/modules/condition_test/src/Plugin/Condition/ConditionTestDualUser.php b/core/modules/system/tests/modules/condition_test/src/Plugin/Condition/ConditionTestDualUser.php
index f331c731e9..81d3e7cea2 100644
--- a/core/modules/system/tests/modules/condition_test/src/Plugin/Condition/ConditionTestDualUser.php
+++ b/core/modules/system/tests/modules/condition_test/src/Plugin/Condition/ConditionTestDualUser.php
@@ -10,7 +10,7 @@
  * @Condition(
  *   id = "condition_test_dual_user",
  *   label = @Translation("Dual user"),
- *   context = {
+ *   context_definitions = {
  *     "user1" = @ContextDefinition("entity:user", label = @Translation("User 1")),
  *     "user2" = @ContextDefinition("entity:user", label = @Translation("User 2"))
  *   }
diff --git a/core/modules/system/tests/modules/condition_test/src/Plugin/Condition/ConditionTestNoExistingType.php b/core/modules/system/tests/modules/condition_test/src/Plugin/Condition/ConditionTestNoExistingType.php
index ef00053fe3..f465916e84 100644
--- a/core/modules/system/tests/modules/condition_test/src/Plugin/Condition/ConditionTestNoExistingType.php
+++ b/core/modules/system/tests/modules/condition_test/src/Plugin/Condition/ConditionTestNoExistingType.php
@@ -10,7 +10,7 @@
  * @Condition(
  *   id = "condition_test_no_existing_type",
  *   label = @Translation("No existing type"),
- *   context = {
+ *   context_definitions = {
  *     "no_existing_type" = @ContextDefinition("no_existing_type", label = @Translation("No existing type")),
  *   }
  * )
diff --git a/core/modules/system/tests/modules/condition_test/src/Plugin/Condition/OptionalContextCondition.php b/core/modules/system/tests/modules/condition_test/src/Plugin/Condition/OptionalContextCondition.php
index 061261c210..46f48d24a1 100644
--- a/core/modules/system/tests/modules/condition_test/src/Plugin/Condition/OptionalContextCondition.php
+++ b/core/modules/system/tests/modules/condition_test/src/Plugin/Condition/OptionalContextCondition.php
@@ -13,7 +13,7 @@
  * @Condition(
  *   id = "condition_test_optional_context",
  *   label = @Translation("Optional context"),
- *   context = {
+ *   context_definitions = {
  *     "node" = @ContextDefinition("entity:node", label = @Translation("Node"), required = FALSE),
  *   }
  * )
diff --git a/core/modules/user/src/Plugin/Condition/UserRole.php b/core/modules/user/src/Plugin/Condition/UserRole.php
index 60b8b0e29c..11ee277970 100644
--- a/core/modules/user/src/Plugin/Condition/UserRole.php
+++ b/core/modules/user/src/Plugin/Condition/UserRole.php
@@ -11,7 +11,7 @@
  * @Condition(
  *   id = "user_role",
  *   label = @Translation("User Role"),
- *   context = {
+ *   context_definitions = {
  *     "user" = @ContextDefinition("entity:user", label = @Translation("User"))
  *   }
  * )
diff --git a/core/modules/views/src/Plugin/Derivative/ViewsBlock.php b/core/modules/views/src/Plugin/Derivative/ViewsBlock.php
index f4da73d4bd..51993ae402 100644
--- a/core/modules/views/src/Plugin/Derivative/ViewsBlock.php
+++ b/core/modules/views/src/Plugin/Derivative/ViewsBlock.php
@@ -115,7 +115,7 @@ public function getDerivativeDefinitions($base_plugin_definition) {
           foreach ($display->getHandlers('argument') as $argument_name => $argument) {
             /** @var \Drupal\views\Plugin\views\argument\ArgumentPluginBase $argument */
             if ($context_definition = $argument->getContextDefinition()) {
-              $this->derivatives[$delta]['context'][$argument_name] = $context_definition;
+              $this->derivatives[$delta]['context_definitions'][$argument_name] = $context_definition;
             }
           }
 
diff --git a/core/tests/Drupal/Tests/Core/Plugin/ContextHandlerTest.php b/core/tests/Drupal/Tests/Core/Plugin/ContextHandlerTest.php
index b4e1eb5e35..3c49a6a2cb 100644
--- a/core/tests/Drupal/Tests/Core/Plugin/ContextHandlerTest.php
+++ b/core/tests/Drupal/Tests/Core/Plugin/ContextHandlerTest.php
@@ -220,7 +220,7 @@ public function providerTestFilterPluginDefinitionsByContexts() {
     $data[] = [FALSE, $plugins, $plugins];
 
     $plugins = [
-      'expected_array_plugin' => ['context' => []],
+      'expected_array_plugin' => ['context_definitions' => []],
       'expected_object_plugin' => new ContextAwarePluginDefinition(),
     ];
     // No context, all plugins available.
@@ -228,7 +228,7 @@ public function providerTestFilterPluginDefinitionsByContexts() {
 
     $plugins = [
       'expected_array_plugin' => [
-        'context' => ['context1' => new ContextDefinition('string')],
+        'context_definitions' => ['context1' => new ContextDefinition('string')],
       ],
       'expected_object_plugin' => (new ContextAwarePluginDefinition())
         ->addContextDefinition('context1', new ContextDefinition('string')),
@@ -241,7 +241,7 @@ public function providerTestFilterPluginDefinitionsByContexts() {
     $mismatched_context_definition = (new ContextDefinition('expected_data_type'))->setConstraints(['mismatched_constraint_name' => 'mismatched_constraint_value']);
     $plugins = [
       'expected_array_plugin' => [
-        'context' => ['context1' => $mismatched_context_definition],
+        'context_definitions' => ['context1' => $mismatched_context_definition],
       ],
       'expected_object_plugin' => (new ContextAwarePluginDefinition())
         ->addContextDefinition('context1', $mismatched_context_definition),
@@ -253,7 +253,7 @@ public function providerTestFilterPluginDefinitionsByContexts() {
     $optional_mismatched_context_definition->setRequired(FALSE);
     $plugins = [
       'expected_array_plugin' => [
-        'context' => ['context1' => $optional_mismatched_context_definition],
+        'context_definitions' => ['context1' => $optional_mismatched_context_definition],
       ],
       'expected_object_plugin' => (new ContextAwarePluginDefinition())
         ->addContextDefinition('context1', $optional_mismatched_context_definition),
@@ -264,7 +264,7 @@ public function providerTestFilterPluginDefinitionsByContexts() {
     $expected_context_definition = (new ContextDefinition('string'))->setConstraints(['Blank' => []]);
     $plugins = [
       'expected_array_plugin' => [
-        'context' => ['context1' => $expected_context_definition],
+        'context_definitions' => ['context1' => $expected_context_definition],
       ],
       'expected_object_plugin' => (new ContextAwarePluginDefinition())
         ->addContextDefinition('context1', $expected_context_definition),
@@ -276,7 +276,7 @@ public function providerTestFilterPluginDefinitionsByContexts() {
     $optional_expected_context_definition->setRequired(FALSE);
     $plugins = [
       'expected_array_plugin' => [
-        'context' => ['context1' => $optional_expected_context_definition],
+        'context_definitions' => ['context1' => $optional_expected_context_definition],
       ],
       'expected_object_plugin' => (new ContextAwarePluginDefinition())
         ->addContextDefinition('context1', $optional_expected_context_definition),
@@ -287,10 +287,10 @@ public function providerTestFilterPluginDefinitionsByContexts() {
     $unexpected_context_definition = (new ContextDefinition('unexpected_data_type'))->setConstraints(['mismatched_constraint_name' => 'mismatched_constraint_value']);
     $plugins = [
       'unexpected_array_plugin' => [
-        'context' => ['context1' => $unexpected_context_definition],
+        'context_definitions' => ['context1' => $unexpected_context_definition],
       ],
       'expected_array_plugin' => [
-        'context' => ['context2' => new ContextDefinition('string')],
+        'context_definitions' => ['context2' => new ContextDefinition('string')],
       ],
       'unexpected_object_plugin' => (new ContextAwarePluginDefinition())
         ->addContextDefinition('context1', $unexpected_context_definition),
@@ -310,6 +310,34 @@ public function providerTestFilterPluginDefinitionsByContexts() {
     return $data;
   }
 
+  /**
+   * @covers ::filterPluginDefinitionsByContexts
+   *
+   * @group legacy
+   */
+  public function testFilterPluginDefinitionsByContextsLegacy() {
+    $plugins = [
+      'unexpected_array_plugin' => [
+        'context' => ['context1' => (new ContextDefinition('unexpected_data_type'))->setConstraints(['mismatched_constraint_name' => 'mismatched_constraint_value'])],
+      ],
+      'expected_array_plugin' => [
+        'context' => ['context2' => new ContextDefinition('string')],
+      ],
+    ];
+    // Context only satisfies one plugin.
+    $expected = [
+      'expected_array_plugin' => $plugins['expected_array_plugin'],
+    ];
+
+    $context = $this->getMock('Drupal\Core\Plugin\Context\ContextInterface');
+    $expected_context_definition = (new ContextDefinition('string'));
+    $context->expects($this->atLeastOnce())
+      ->method('getContextDefinition')
+      ->willReturn($expected_context_definition);
+
+    $this->assertSame($expected, $this->contextHandler->filterPluginDefinitionsByContexts([$context], $plugins));
+  }
+
   /**
    * @covers ::applyContextMapping
    */