diff --git a/controller/contactcontroller.php b/controller/contactcontroller.php
index fdb5526632..935697d7d1 100644
--- a/controller/contactcontroller.php
+++ b/controller/contactcontroller.php
@@ -116,13 +116,13 @@ public function searchAttendee($search) {
 				$r['EMAIL'] = [$r['EMAIL']];
 			}
 
-			$lang = $this->getPreferredLanguageFromUidOrDefault($r['UID'], $defaultLang);
+			$language = $this->getPreferredLanguageFromUidOrDefault($r['UID'], $defaultLang);
 			$isLocalUser = isset($r['isLocalSystemBook']) && $r['isLocalSystemBook'];
 
 			$contacts[] = [
 					'email' => $r['EMAIL'],
 					'name' => $name,
-					'lang' => $lang
+					'lang' => $language
 			];
 		}
 
@@ -153,6 +153,6 @@ private function getNameFromContact(array $r) {
 	 * @return string
 	 */
 	private function getPreferredLanguageFromUidOrDefault($uid, $default) {
-		return $this->config->getUserValue($uid, 'core', 'lang', $default);
+		return $this->config->getUserValue($uid, 'core', 'language', $default);
 	}
 }
diff --git a/controller/viewcontroller.php b/controller/viewcontroller.php
index 82a80413ec..55e3a24bbe 100644
--- a/controller/viewcontroller.php
+++ b/controller/viewcontroller.php
@@ -133,30 +133,30 @@ public function index() {
 			return [];
 		}
 
-		$userLang = $this->config->getUserValue($userId, 'core', 'lang', $this->l10nFactory->findLanguage());
+		$userLang = $this->config->getUserValue($userId, 'core', 'language', $this->l10nFactory->findLanguage());
 		$languageCodes = $this->l10nFactory->findAvailableLanguages();
 
 		$commonLanguages = [];
 		$languages = [];
 
-		foreach($languageCodes as $lang) {
-			$l = \OC::$server->getL10N('settings', $lang);
+		foreach($languageCodes as $language) {
+			$l = \OC::$server->getL10N('settings', $language);
 			// TRANSLATORS this is the language name for the language switcher in the personal settings and should be the localized version
 			$potentialName = (string) $l->t('__language_name__');
-			if($l->getLanguageCode() === $lang && substr($potentialName, 0, 1) !== '_') {//first check if the language name is in the translation file
-				$ln = array('code' => $lang, 'name' => $potentialName);
-			} elseif ($lang === 'en') {
-				$ln = ['code' => $lang, 'name' => 'English (US)'];
+			if($l->getLanguageCode() === $language && substr($potentialName, 0, 1) !== '_') {//first check if the language name is in the translation file
+				$ln = array('code' => $language, 'name' => $potentialName);
+			} elseif ($language === 'en') {
+				$ln = ['code' => $language, 'name' => 'English (US)'];
 			}else{//fallback to language code
-				$ln=array('code'=>$lang, 'name'=>$lang);
+				$ln=array('code'=>$language, 'name'=>$language);
 			}
 
 			// put appropriate languages into appropriate arrays, to print them sorted
 			// used language -> common languages -> divider -> other languages
-			if ($lang === $userLang) {
+			if ($language === $userLang) {
 				$userLang = $ln;
-			} elseif (in_array($lang, self::COMMON_LANGUAGE_CODES)) {
-				$commonLanguages[array_search($lang, self::COMMON_LANGUAGE_CODES)]=$ln;
+			} elseif (in_array($language, self::COMMON_LANGUAGE_CODES)) {
+				$commonLanguages[array_search($language, self::COMMON_LANGUAGE_CODES)]=$ln;
 			} else {
 				$languages[]=$ln;
 			}
diff --git a/js/app/controllers/attendeecontroller.js b/js/app/controllers/attendeecontroller.js
index ede7e4bca9..f7becc8a3f 100644
--- a/js/app/controllers/attendeecontroller.js
+++ b/js/app/controllers/attendeecontroller.js
@@ -63,7 +63,7 @@ app.controller('AttendeeController', function($scope, AutoCompletionService) {
 					'rsvp': 'TRUE',
 					'partstat': 'NEEDS-ACTION',
 					'cutype': 'INDIVIDUAL',
-					'lang': OC.getLocale() // Use current user's timezone as a default value
+					'language': OC.getLocale() // Use current user's timezone as a default value
 				}
 			});
 		}
@@ -98,7 +98,7 @@ app.controller('AttendeeController', function($scope, AutoCompletionService) {
 						displayname: displayname,
 						email: email,
 						name: attendee.name,
-						lang: attendee.lang
+						language: attendee.language
 					});
 				});
 			});
@@ -117,7 +117,7 @@ app.controller('AttendeeController', function($scope, AutoCompletionService) {
 				rsvp: 'TRUE',
 				partstat: 'NEEDS-ACTION',
 				cutype: 'INDIVIDUAL',
-				lang: item.lang
+				language: item.language
 			}
 		});
 		$scope.nameofattendee = '';
diff --git a/js/app/models/simpleEventModel.js b/js/app/models/simpleEventModel.js
index 99ab9da309..692c3e8c0f 100644
--- a/js/app/models/simpleEventModel.js
+++ b/js/app/models/simpleEventModel.js
@@ -52,7 +52,7 @@ app.factory('SimpleEvent', function () {
 		'cn',
 		'delegated-from',
 		'delegated-to',
-		'lang'
+		'language'
 	];
 
 	const organizerParameters = [