diff --git a/core/lib/Drupal/Core/DrupalKernel.php b/core/lib/Drupal/Core/DrupalKernel.php
index b608ddcd934f..d54f07cae751 100644
--- a/core/lib/Drupal/Core/DrupalKernel.php
+++ b/core/lib/Drupal/Core/DrupalKernel.php
@@ -535,7 +535,7 @@ class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
     // Set the allowed protocols.
     UrlHelper::setAllowedProtocols($this->container->getParameter('filter_protocols'));
 
-    // Override of Symfony's mime type guesser singleton.
+    // Override of Symfony's MIME type guesser singleton.
     MimeTypeGuesser::registerWithSymfonyGuesser($this->container);
 
     $this->prepared = TRUE;
diff --git a/core/lib/Drupal/Core/File/MimeType/MimeTypeGuesser.php b/core/lib/Drupal/Core/File/MimeType/MimeTypeGuesser.php
index ae750502c4bd..5de0e1e65eb1 100644
--- a/core/lib/Drupal/Core/File/MimeType/MimeTypeGuesser.php
+++ b/core/lib/Drupal/Core/File/MimeType/MimeTypeGuesser.php
@@ -109,7 +109,7 @@ class MimeTypeGuesser implements MimeTypeGuesserInterface {
   }
 
   /**
-   * A helper function to register with Symfony's singleton mime type guesser.
+   * A helper function to register with Symfony's singleton MIME type guesser.
    *
    * Symfony's default mimetype guessers have dependencies on PHP's fileinfo
    * extension or being able to run the system command file. Drupal's guesser
diff --git a/core/modules/file/config/optional/views.view.files.yml b/core/modules/file/config/optional/views.view.files.yml
index e5e30bd60808..e5edee2e4032 100644
--- a/core/modules/file/config/optional/views.view.files.yml
+++ b/core/modules/file/config/optional/views.view.files.yml
@@ -247,7 +247,7 @@ display:
           relationship: none
           group_type: group
           admin_label: ''
-          label: 'Mime type'
+          label: 'MIME type'
           exclude: false
           alter:
             alter_text: false
@@ -623,7 +623,7 @@ display:
           exposed: true
           expose:
             operator_id: filemime_op
-            label: 'Mime type'
+            label: 'MIME type'
             description: ''
             use_operator: false
             operator: filemime_op
diff --git a/core/modules/file/file.module b/core/modules/file/file.module
index bffb84d27ea3..310eb26c2369 100644
--- a/core/modules/file/file.module
+++ b/core/modules/file/file.module
@@ -1266,7 +1266,7 @@ function template_preprocess_file_link(&$variables) {
     'file',
     // Add a specific class for each and every mime type.
     'file--mime-' . strtr($mime_type, array('/' => '-', '.' => '-')),
-    // Add a more general class for groups of well known mime types.
+    // Add a more general class for groups of well known MIME types.
     'file--' . file_icon_class($mime_type),
   );
 
diff --git a/core/modules/file/src/Plugin/Field/FieldFormatter/FilemimeFormatter.php b/core/modules/file/src/Plugin/Field/FieldFormatter/FilemimeFormatter.php
index 5e2925117570..3c1ce1713393 100644
--- a/core/modules/file/src/Plugin/Field/FieldFormatter/FilemimeFormatter.php
+++ b/core/modules/file/src/Plugin/Field/FieldFormatter/FilemimeFormatter.php
@@ -12,11 +12,11 @@ use Drupal\Core\Field\FieldItemInterface;
 use Drupal\Core\Form\FormStateInterface;
 
 /**
- * Formatter to render the file mime type, with an optional icon.
+ * Formatter to render the file MIME type, with an optional icon.
  *
  * @FieldFormatter(
  *   id = "file_filemime",
- *   label = @Translation("File mime"),
+ *   label = @Translation("File MIME"),
  *   field_types = {
  *     "string"
  *   }
diff --git a/core/modules/file/src/Plugin/migrate/source/d6/File.php b/core/modules/file/src/Plugin/migrate/source/d6/File.php
index 3bb7708bf834..0ec75dd5258f 100644
--- a/core/modules/file/src/Plugin/migrate/source/d6/File.php
+++ b/core/modules/file/src/Plugin/migrate/source/d6/File.php
@@ -85,7 +85,7 @@ class File extends DrupalSqlBase {
       'uid' => $this->t('The {users}.uid who added the file. If set to 0, this file was added by an anonymous user.'),
       'filename' => $this->t('File name'),
       'filepath' => $this->t('File path'),
-      'filemime' => $this->t('File Mime Type'),
+      'filemime' => $this->t('File MIME Type'),
       'status' => $this->t('The published status of a file.'),
       'timestamp' => $this->t('The time that the file was added.'),
       'file_directory_path' => $this->t('The Drupal files path.'),
diff --git a/core/modules/file/src/Plugin/migrate/source/d7/File.php b/core/modules/file/src/Plugin/migrate/source/d7/File.php
index 129fa62fab50..0fcb9e3880ee 100644
--- a/core/modules/file/src/Plugin/migrate/source/d7/File.php
+++ b/core/modules/file/src/Plugin/migrate/source/d7/File.php
@@ -105,7 +105,7 @@ class File extends DrupalSqlBase {
       'uid' => $this->t('The {users}.uid who added the file. If set to 0, this file was added by an anonymous user.'),
       'filename' => $this->t('File name'),
       'filepath' => $this->t('File path'),
-      'filemime' => $this->t('File Mime Type'),
+      'filemime' => $this->t('File MIME Type'),
       'status' => $this->t('The published status of a file.'),
       'timestamp' => $this->t('The time that the file was added.'),
     );
diff --git a/core/modules/hal/src/Tests/FileDenormalizeTest.php b/core/modules/hal/src/Tests/FileDenormalizeTest.php
index b2e6ab59c7ac..74e11bb3fc50 100644
--- a/core/modules/hal/src/Tests/FileDenormalizeTest.php
+++ b/core/modules/hal/src/Tests/FileDenormalizeTest.php
@@ -50,7 +50,7 @@ class FileDenormalizeTest extends WebTestBase {
     $this->assertTrue(file_exists($denormalized->getFileUri()), 'The temporary file was found.');
 
     $this->assertIdentical($file->uuid(), $denormalized->uuid(), 'The expected UUID was found');
-    $this->assertIdentical($file->getMimeType(), $denormalized->getMimeType(), 'The expected mime type was found.');
+    $this->assertIdentical($file->getMimeType(), $denormalized->getMimeType(), 'The expected MIME type was found.');
     $this->assertIdentical($file->getFilename(), $denormalized->getFilename(), 'The expected filename was found.');
     $this->assertTrue($denormalized->isPermanent(), 'The file has a permanent status.');
 
@@ -72,7 +72,7 @@ class FileDenormalizeTest extends WebTestBase {
     $this->assertIdentical('temporary://' . $file_name, $denormalized->getFileUri(), 'The expected file URI was found.');
     $this->assertTrue(file_exists($denormalized->getFileUri()), 'The temporary file was found.');
 
-    $this->assertIdentical('text/plain', $denormalized->getMimeType(), 'The expected mime type was found.');
+    $this->assertIdentical('text/plain', $denormalized->getMimeType(), 'The expected MIME type was found.');
     $this->assertIdentical($file_name, $denormalized->getFilename(), 'The expected filename was found.');
     $this->assertFalse($denormalized->isPermanent(), 'The file has a permanent status.');
   }