diff -u b/core/lib/Drupal/Core/Entity/ContentEntityDatabaseStorage.php b/core/lib/Drupal/Core/Entity/ContentEntityDatabaseStorage.php
--- b/core/lib/Drupal/Core/Entity/ContentEntityDatabaseStorage.php
+++ b/core/lib/Drupal/Core/Entity/ContentEntityDatabaseStorage.php
@@ -960,7 +960,7 @@
       $definitions[$bundle] = $this->entityManager->getFieldDefinitions($this->entityTypeId, $bundle);
       foreach ($definitions[$bundle] as $field_name => $instance) {
         if ($instance instanceof FieldInstanceConfigInterface) {
-          $fields[$field_name] = $instance->getField();
+          $fields[$field_name] = $instance->getFieldStorageDefinition();
         }
       }
     }
@@ -1030,7 +1030,7 @@
       if (!($instance instanceof FieldInstanceConfigInterface)) {
         continue;
       }
-      $field = $instance->getField();
+      $field = $instance->getFieldStorageDefinition();
       $table_name = static::_fieldTableName($field);
       $revision_name = static::_fieldRevisionTableName($field);
 
@@ -1107,7 +1107,7 @@
       if (!($instance instanceof FieldInstanceConfigInterface)) {
         continue;
       }
-      $field = $instance->getField();
+      $field = $instance->getFieldStorageDefinition();
       $table_name = static::_fieldTableName($field);
       $revision_name = static::_fieldRevisionTableName($field);
       $this->database->delete($table_name)
@@ -1129,7 +1129,7 @@
         if (!($instance instanceof FieldInstanceConfigInterface)) {
           continue;
         }
-        $revision_name = static::_fieldRevisionTableName($instance->getField());
+        $revision_name = static::_fieldRevisionTableName($instance->getFieldStorageDefinition());
         $this->database->delete($revision_name)
           ->condition('entity_id', $entity->id())
           ->condition('revision_id', $vid)
@@ -1260,7 +1260,7 @@
    * {@inheritdoc}
    */
   public function onInstanceDelete(FieldInstanceConfigInterface $instance) {
-    $field = $instance->getField();
+    $field = $instance->getFieldStorageDefinition();
     $table_name = static::_fieldTableName($field);
     $revision_name = static::_fieldRevisionTableName($field);
     $this->database->update($table_name)
@@ -1282,7 +1282,7 @@
     // using the old bundle name.
     $instances = entity_load_multiple_by_properties('field_instance_config', array('entity_type' => $this->entityTypeId, 'bundle' => $bundle, 'include_deleted' => TRUE));
     foreach ($instances as $instance) {
-      $field = $instance->getField();
+      $field = $instance->getFieldStorageDefinition();
       $table_name = static::_fieldTableName($field);
       $revision_name = static::_fieldRevisionTableName($field);
       $this->database->update($table_name)
@@ -1300,7 +1300,7 @@
    * {@inheritdoc}
    */
   protected function readFieldItemsToPurge(EntityInterface $entity, FieldInstanceConfigInterface $instance) {
-    $field = $instance->getField();
+    $field = $instance->getFieldStorageDefinition();
     $table_name = static::_fieldTableName($field);
     $query = $this->database->select($table_name, 't', array('fetch' => \PDO::FETCH_ASSOC))
       ->condition('entity_id', $entity->id())
@@ -1315,7 +1315,7 @@
    * {@inheritdoc}
    */
   public function purgeFieldItems(EntityInterface $entity, FieldInstanceConfigInterface $instance) {
-    $field = $instance->getField();
+    $field = $instance->getFieldStorageDefinition();
     $table_name = static::_fieldTableName($field);
     $revision_name = static::_fieldRevisionTableName($field);
     $this->database->delete($table_name)
diff -u b/core/lib/Drupal/Core/Field/FieldDefinition.php b/core/lib/Drupal/Core/Field/FieldDefinition.php
--- b/core/lib/Drupal/Core/Field/FieldDefinition.php
+++ b/core/lib/Drupal/Core/Field/FieldDefinition.php
@@ -594,2 +594,9 @@
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getFieldStorageDefinition() {
+    return $this;
+  }
+
 }
diff -u b/core/lib/Drupal/Core/Field/FieldDefinitionInterface.php b/core/lib/Drupal/Core/Field/FieldDefinitionInterface.php
--- b/core/lib/Drupal/Core/Field/FieldDefinitionInterface.php
+++ b/core/lib/Drupal/Core/Field/FieldDefinitionInterface.php
@@ -57,2 +57,23 @@
   /**
+   * Returns the machine name of the field.
+   *
+   * This defines how the field data is accessed from the entity. For example,
+   * if the field name is "foo", then $entity->foo returns its data.
+   *
+   * @return string
+   *   The field name.
+   */
+  public function getName();
+
+  /**
+   * Returns the field type.
+   *
+   * @return string
+   *   The field type, i.e. the id of a field type plugin. For example 'text'.
+   *
+   * @see \Drupal\Core\Field\FieldTypePluginManagerInterface
+   */
+  public function getType();
+
+  /**
    * Returns whether the display for the field can be configured.
@@ -149,2 +170,9 @@
 
+  /**
+   * Returns the field storage definition.
+   *
+   * @return \Drupal\Core\Field\FieldStorageDefinitionInterface
+   *   The field storage definition.
+   */
+  public function getFieldStorageDefinition();
 }
diff -u b/core/lib/Drupal/Core/Field/FieldItemList.php b/core/lib/Drupal/Core/Field/FieldItemList.php
--- b/core/lib/Drupal/Core/Field/FieldItemList.php
+++ b/core/lib/Drupal/Core/Field/FieldItemList.php
@@ -285,7 +285,7 @@
     // Check that the number of values doesn't exceed the field cardinality. For
     // form submitted values, this can only happen with 'multiple value'
     // widgets.
-    $cardinality = $this->getFieldDefinition()->getCardinality();
+    $cardinality = $this->getFieldDefinition()->getFieldStorageDefinition()->getCardinality();
     if ($cardinality != FieldStorageDefinitionInterface::CARDINALITY_UNLIMITED) {
       $constraints[] = \Drupal::typedDataManager()
         ->getValidationConstraintManager()
diff -u b/core/lib/Drupal/Core/Field/WidgetBase.php b/core/lib/Drupal/Core/Field/WidgetBase.php
--- b/core/lib/Drupal/Core/Field/WidgetBase.php
+++ b/core/lib/Drupal/Core/Field/WidgetBase.php
@@ -137,7 +137,7 @@
    */
   protected function formMultipleElements(FieldItemListInterface $items, array &$form, array &$form_state) {
     $field_name = $this->fieldDefinition->getName();
-    $cardinality = $this->fieldDefinition->getCardinality();
+    $cardinality = $this->fieldDefinition->getFieldStorageDefinition()->getCardinality();
     $parents = $form['#parents'];
 
     // Determine the number of widgets to display.
@@ -193,7 +193,7 @@
         '#theme' => 'field_multiple_value_form',
         '#field_name' => $field_name,
         '#cardinality' => $cardinality,
-        '#cardinality_multiple' => $this->fieldDefinition->isMultiple(),
+        '#cardinality_multiple' => $this->fieldDefinition->getFieldStorageDefinition()->isMultiple(),
         '#required' => $this->fieldDefinition->isRequired(),
         '#title' => $title,
         '#description' => $description,
diff -u b/core/modules/content_translation/content_translation.module b/core/modules/content_translation/content_translation.module
--- b/core/modules/content_translation/content_translation.module
+++ b/core/modules/content_translation/content_translation.module
@@ -642,7 +642,7 @@
     '#default_value' => $instance->isTranslatable(),
     '#weight' => -1,
     '#disabled' => !$bundle_is_translatable,
-    '#access' => $instance->getField()->isTranslatable(),
+    '#access' => $instance->getFieldStorageDefinition()->isTranslatable(),
   );
 
   // Provide helpful pointers for administrators.
diff -u b/core/modules/field/src/Entity/FieldInstanceConfig.php b/core/modules/field/src/Entity/FieldInstanceConfig.php
--- b/core/modules/field/src/Entity/FieldInstanceConfig.php
+++ b/core/modules/field/src/Entity/FieldInstanceConfig.php
@@ -276,6 +276,21 @@
   /**
    * {@inheritdoc}
    */
+  public function getName() {
+    return $this->field_name;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getType() {
+    return $this->getFieldStorageDefinition()->getType();
+  }
+
+
+  /**
+   * {@inheritdoc}
+   */
   public function toArray() {
     $properties = parent::toArray();
     // Additionally, include the field type, that is needed to be able to
@@ -291,7 +306,7 @@
   public function postCreate(EntityStorageInterface $storage) {
     // Validate that we have a valid field for this instance. This throws an
     // exception if the field is invalid.
-    $field = $this->getField();
+    $field = $this->getFieldStorageDefinition();
 
     // Make sure the field_uuid is populated.
     $this->field_uuid = $field->uuid();
@@ -299,7 +314,7 @@
     // 'Label' defaults to the field name (mostly useful for field instances
     // created in tests).
     if (empty($this->label)) {
-      $this->label = $this->field->name;
+      $this->label = $this->getName();
     }
   }
 
@@ -315,7 +330,7 @@
     $entity_manager = \Drupal::entityManager();
     $field_type_manager = \Drupal::service('plugin.manager.field.field_type');
 
-    $field = $this->getField();
+    $field = $this->getFieldStorageDefinition();
 
     if ($this->isNew()) {
       // Set the default instance settings.
@@ -351,7 +366,7 @@
   public function calculateDependencies() {
     parent::calculateDependencies();
     // Manage dependencies.
-    $this->addDependency('entity', $this->getField()->getConfigDependencyName());
+    $this->addDependency('entity', $this->getFieldStorageDefinition()->getConfigDependencyName());
     $bundle_entity_type_id = \Drupal::entityManager()->getDefinition($this->entity_type)->getBundleEntityType();
     if ($bundle_entity_type_id != 'bundle') {
       // If the target entity type uses entities to manage its bundles then
@@ -371,7 +386,7 @@
 
     // Invalidate the render cache for all affected entities.
     $entity_manager = \Drupal::entityManager();
-    $entity_type = $this->getTargetEntityTypeId();
+    $entity_type = $this->getFieldStorageDefinition()->getTargetEntityTypeId();
     if ($entity_manager->hasController($entity_type, 'view_builder')) {
       $entity_manager->getViewBuilder($entity_type)->resetCache();
     }
@@ -422,7 +437,7 @@
     // Delete fields that have no more instances.
     $fields_to_delete = array();
     foreach ($instances as $instance) {
-      $field = $instance->getField();
+      $field = $instance->getFieldStorageDefinition();
       if (!$instance->deleted && empty($instance->noFieldDelete) && !$instance->isUninstalling() && count($field->getBundles()) == 0) {
         // Key by field UUID to avoid deleting the same field twice.
         $fields_to_delete[$instance->field_uuid] = $field;
@@ -459,7 +474,7 @@
   /**
    * {@inheritdoc}
    */
-  public function getField() {
+  public function getFieldStorageDefinition() {
     if (!$this->field) {
       $fields = \Drupal::entityManager()->getFieldStorageDefinitions($this->entity_type);
       if (!isset($fields[$this->field_name])) {
@@ -477,22 +492,8 @@
   /**
    * {@inheritdoc}
    */
-  public function getName() {
-    return $this->field_name;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function getType() {
-    return $this->getField()->getType();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
   public function getSettings() {
-    return $this->settings + $this->getField()->getSettings();
+    return $this->settings + $this->getFieldStorageDefinition()->getSettings();
   }
 
   /**
@@ -503,23 +504,16 @@
       return $this->settings[$setting_name];
     }
     else {
-      return $this->getField()->getSetting($setting_name);
+      return $this->getFieldStorageDefinition()->getSetting($setting_name);
     }
   }
 
   /**
    * {@inheritdoc}
    */
-  public function getProvider() {
-    return $this->getField()->getProvider();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
   public function isTranslatable() {
     // A field can be enabled for translation only if translation is supported.
-    return $this->translatable && $this->getField()->isTranslatable();
+    return $this->translatable && $this->getFieldStorageDefinition()->isTranslatable();
   }
 
   /**
@@ -534,7 +527,0 @@
-   * {@inheritdoc}
-   */
-  public function isRevisionable() {
-    return $this->getField()->isRevisionable();
-  }
-
-  /**
@@ -581,13 +568,6 @@
   /**
    * {@inheritdoc}
    */
-  public function getCardinality() {
-    return $this->getField()->cardinality;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
   public function isRequired() {
     return $this->required;
   }
@@ -595,13 +575,6 @@
   /**
    * {@inheritdoc}
    */
-  public function isMultiple() {
-    return $this->getField()->isMultiple();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
   public function getDefaultValue(ContentEntityInterface $entity) {
     // Allow custom default values function.
     if ($function = $this->default_value_function) {
@@ -633,20 +606,6 @@
   /**
    * {@inheritdoc}
    */
-  public function getTargetEntityTypeId() {
-    return $this->entity_type;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function isQueryable() {
-    return TRUE;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
   public function allowBundleRename() {
     $this->bundle_rename_allowed = TRUE;
   }
@@ -764,55 +723,6 @@
   /**
    * {@inheritdoc}
    */
-  public function getPropertyDefinition($name) {
-    return $this->getField()->getPropertyDefinition($name);
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function getPropertyDefinitions() {
-    return $this->getField()->getPropertyDefinitions();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function getPropertyNames() {
-    return $this->getField()->getPropertyNames();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function getMainPropertyName() {
-    return $this->getField()->getMainPropertyName();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function getSchema() {
-    return $this->getField()->getSchema();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function getColumns() {
-    return $this->getField()->getColumns();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function hasCustomStorage() {
-    return $this->getField()->hasCustomStorage();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
   public function isDeleted() {
     return $this->deleted;
   }
diff -u b/core/modules/field_ui/src/FieldOverview.php b/core/modules/field_ui/src/FieldOverview.php
--- b/core/modules/field_ui/src/FieldOverview.php
+++ b/core/modules/field_ui/src/FieldOverview.php
@@ -116,7 +116,7 @@
 
     // Fields.
     foreach ($instances as $name => $instance) {
-      $field = $instance->getField();
+      $field = $instance->getFieldStorageDefinition();
       $route_parameters = array(
         $this->bundleEntityType => $this->bundle,
         'field_instance_config' => $instance->id(),
@@ -515,7 +515,7 @@
         // - locked fields,
         // - fields that should not be added via user interface.
         $field_type = $instance->getType();
-        $field = $instance->getField();
+        $field = $instance->getFieldStorageDefinition();
         if (empty($field->locked) && empty($field_types[$field_type]['no_ui'])) {
           $options[$instance->getName()] = array(
             'type' => $field_type,
diff -u b/core/modules/field_ui/src/Form/FieldEditForm.php b/core/modules/field_ui/src/Form/FieldEditForm.php
--- b/core/modules/field_ui/src/Form/FieldEditForm.php
+++ b/core/modules/field_ui/src/Form/FieldEditForm.php
@@ -78,7 +78,7 @@
     $this->instance = $form_state['instance'] = $field_instance_config;
     $form['#title'] = $this->instance->label();
 
-    $field = $this->instance->getField();
+    $field = $this->instance->getFieldStorageDefinition();
     $form['#field'] = $field;
     $form['#bundle'] = $this->instance->bundle;
 
@@ -187,7 +187,7 @@
     unset($field_values['container']);
 
     // Merge incoming form values into the existing field.
-    $field = $this->instance->getField();
+    $field = $this->instance->getFieldStorageDefinition();
     foreach ($field_values as $key => $value) {
       $field->{$key} = $value;
     }
diff -u b/core/modules/image/src/Tests/ImageFieldDisplayTest.php b/core/modules/image/src/Tests/ImageFieldDisplayTest.php
--- b/core/modules/image/src/Tests/ImageFieldDisplayTest.php
+++ b/core/modules/image/src/Tests/ImageFieldDisplayTest.php
@@ -236,7 +236,7 @@
       $field_name . '[0][title]' => $this->randomName($test_size),
     );
     $this->drupalPostForm('node/' . $nid . '/edit', $edit, t('Save and keep published'));
-    $schema = $instance->getField()->getSchema();
+    $schema = $instance->getFieldStorageDefinition()->getSchema();
     $this->assertRaw(t('Alternate text cannot be longer than %max characters but is currently %length characters long.', array(
       '%max' => $schema['columns']['alt']['length'],
       '%length' => $test_size,
only in patch2:
unchanged:
--- a/core/lib/Drupal/Core/Field/TypedData/FieldItemDataDefinition.php
+++ b/core/lib/Drupal/Core/Field/TypedData/FieldItemDataDefinition.php
@@ -61,21 +61,21 @@ public static function create($field_definition) {
    * {@inheritdoc}
    */
   public function getPropertyDefinition($name) {
-    return $this->fieldDefinition->getPropertyDefinition($name);
+    return $this->fieldDefinition->getFieldStorageDefinition()->getPropertyDefinition($name);
   }
 
   /**
    * {@inheritdoc}
    */
   public function getPropertyDefinitions() {
-    return $this->fieldDefinition->getPropertyDefinitions();
+    return $this->fieldDefinition->getFieldStorageDefinition()->getPropertyDefinitions();
   }
 
   /**
    * {@inheritdoc}
    */
   public function getMainPropertyName() {
-    return $this->fieldDefinition->getMainPropertyName();
+    return $this->fieldDefinition->getFieldStorageDefinition()->getMainPropertyName();
   }
 
 }
only in patch2:
unchanged:
--- a/core/modules/field/field.purge.inc
+++ b/core/modules/field/field.purge.inc
@@ -98,7 +98,7 @@ function field_purge_batch($batch_size, $field_uuid = NULL) {
     );
     // Retrieve some entities.
     $query = $factory->get($entity_type)
-      ->condition('id:' . $instance->getField()->uuid() . '.deleted', 1)
+      ->condition('id:' . $instance->getFieldStorageDefinition()->uuid() . '.deleted', 1)
       ->range(0, $batch_size);
     // If there's no bundle key, all results will have the same bundle.
     if ($bundle_key = $info[$entity_type]->getKey('bundle')) {
only in patch2:
unchanged:
--- a/core/modules/field/src/FieldInstanceConfigInterface.php
+++ b/core/modules/field/src/FieldInstanceConfigInterface.php
@@ -21,7 +21,7 @@
    * @return \Drupal\field\FieldConfigInterface
    *   The field entity for this instance.
    */
-  public function getField();
+  public function getFieldStorageDefinition();
 
   /**
    * Allows a bundle to be renamed.
only in patch2:
unchanged:
--- a/core/modules/field/src/FieldInstanceConfigStorage.php
+++ b/core/modules/field/src/FieldInstanceConfigStorage.php
@@ -132,7 +132,7 @@ public function loadByProperties(array $conditions = array()) {
     $matching_instances = array();
     foreach ($instances as $instance) {
       // Some conditions are checked against the field.
-      $field = $instance->getField();
+      $field = $instance->getFieldStorageDefinition();
 
       // Only keep the instance if it matches all conditions.
       foreach ($conditions as $key => $value) {
only in patch2:
unchanged:
--- a/core/modules/field_ui/src/Form/FieldInstanceEditForm.php
+++ b/core/modules/field_ui/src/Form/FieldInstanceEditForm.php
@@ -67,7 +67,7 @@ public function buildForm(array $form, array &$form_state, FieldInstanceConfigIn
 
     $bundle = $this->instance->bundle;
     $entity_type = $this->instance->entity_type;
-    $field = $this->instance->getField();
+    $field = $this->instance->getFieldStorageDefinition();
     $bundles = entity_get_bundles();
 
     $form_title = $this->t('%instance settings for %bundle', array(
only in patch2:
unchanged:
--- a/core/modules/image/image.module
+++ b/core/modules/image/image.module
@@ -440,7 +440,7 @@ function image_field_config_update(FieldConfigInterface $field) {
  * Implements hook_ENTITY_TYPE_update() for 'field_instance_config'.
  */
 function image_field_instance_config_update(FieldInstanceConfigInterface $field_instance) {
-  $field = $field_instance->getField();
+  $field = $field_instance->getFieldStorageDefinition();
   if ($field->type != 'image') {
     // Only act on image fields.
     return;
@@ -494,7 +494,7 @@ function image_field_config_delete(FieldConfigInterface $field) {
  * Implements hook_ENTITY_TYPE_delete() for 'field_instance_config'.
  */
 function image_field_instance_config_delete(FieldInstanceConfigInterface $field_instance) {
-  $field = $field_instance->getField();
+  $field = $field_instance->getFieldStorageDefinition();
   if ($field->type != 'image') {
     // Only act on image fields.
     return;
only in patch2:
unchanged:
--- a/core/modules/image/src/Tests/ImageFieldDefaultImagesTest.php
+++ b/core/modules/image/src/Tests/ImageFieldDefaultImagesTest.php
@@ -77,7 +77,7 @@ public function testDefaultImages() {
     $instance_field_settings = $instance->getSettings();
     $this->assertEqual($instance_field_settings['default_image']['fid'], $default_images['instance']->id());
 
-    $field = $instance->getField();
+    $field = $instance->getFieldStorageDefinition();
 
     // The field default image id should be 1.
     $default_image = $field->getSetting('default_image');
only in patch2:
unchanged:
--- a/core/modules/options/src/Plugin/Field/FieldWidget/OptionsWidgetBase.php
+++ b/core/modules/options/src/Plugin/Field/FieldWidget/OptionsWidgetBase.php
@@ -47,7 +47,7 @@
    */
   public function __construct($plugin_id, $plugin_definition, FieldDefinitionInterface $field_definition, array $settings) {
     parent::__construct($plugin_id, $plugin_definition, $field_definition, $settings);
-    $property_names = $this->fieldDefinition->getPropertyNames();
+    $property_names = $this->fieldDefinition->getFieldStorageDefinition()->getPropertyNames();
     $this->column = $property_names[0];
   }
 
@@ -58,7 +58,7 @@ public function formElement(FieldItemListInterface $items, $delta, array $elemen
     // Prepare some properties for the child methods to build the actual form
     // element.
     $this->required = $element['#required'];
-    $this->multiple = $this->fieldDefinition->isMultiple();
+    $this->multiple = $this->fieldDefinition->getFieldStorageDefinition()->isMultiple();
     $this->has_value = isset($items[0]->{$this->column});
 
     // Add our custom validator.
only in patch2:
unchanged:
--- a/core/modules/system/src/Tests/Entity/EntityFieldTest.php
+++ b/core/modules/system/src/Tests/Entity/EntityFieldTest.php
@@ -399,7 +399,7 @@ protected function checkIntrospection($entity_type) {
     $this->assertEqual($userref_properties['target_id']->getDataType(), 'integer', $entity_type .': Entity id property of the user found.');
     $this->assertEqual($userref_properties['entity']->getDataType(), 'entity_reference', $entity_type .': Entity reference property of the user found.');
 
-    $textfield_properties = $entity->field_test_text->getFieldDefinition()->getPropertyDefinitions();
+    $textfield_properties = $entity->field_test_text->getFieldDefinition()->getFieldStorageDefinition()->getPropertyDefinitions();
     $this->assertEqual($textfield_properties['value']->getDataType(), 'string', $entity_type .': String value property of the test-text field found.');
     $this->assertEqual($textfield_properties['format']->getDataType(), 'filter_format', $entity_type .': String format field of the test-text field found.');
     $this->assertEqual($textfield_properties['processed']->getDataType(), 'string', $entity_type .': String processed property of the test-text field found.');