diff --git a/action.yml b/action.yml
index 2cefbe8..c6a6d97 100644
--- a/action.yml
+++ b/action.yml
@@ -81,7 +81,7 @@ inputs:
     required: false
     default: true
   LANGUAGES:
-    description: 'A collection of comma-delimited URLs or local paths starting from the current working directory of the action for costume languages'
+    description: 'A collection of comma-delimited URLs or local paths starting from the current working directory of the action for custom languages'
     required: false
     default: ''
   NO_STANDARD:
diff --git a/main.py b/main.py
index ab155a6..31ef7b5 100644
--- a/main.py
+++ b/main.py
@@ -337,22 +337,22 @@ class TodoParser(object):
             self.syntax_dict = []
             self.languages_dict = {}
 
-        costume_languages = os.getenv('INPUT_LANGUAGES', '')
-        if costume_languages != '':
-            # Load all costume languages
-            for path in costume_languages.split(','):
+        custom_languages = os.getenv('INPUT_LANGUAGES', '')
+        if custom_languages != '':
+            # Load all custom languages
+            for path in custom_languages.split(','):
                 try:
                     # Decide if the path is a url or local file
                     if path.startswith('http'):
                         languages_request = requests.get(path)
                         if languages_request.status_code != 200:
-                            print('Cannot retrieve costume language file. (\''+path+'\')')
+                            print('Cannot retrieve custom language file. (\''+path+'\')')
                             continue
                         data = languages_request.json()
                     else:
                         path = os.path.join(os.getcwd(), path)
                         if not os.path.exists(path) or not os.path.isfile(path):
-                            print('Cannot retrieve costume language file. (\''+path+'\')')
+                            print('Cannot retrieve custom language file. (\''+path+'\')')
                             continue
                         f = open(path)
                         data = json.load(f)
diff --git a/tests/costume_languages.json b/tests/custom_languages.json
similarity index 100%
rename from tests/costume_languages.json
rename to tests/custom_languages.json
diff --git a/tests/test_todo_parser.py b/tests/test_todo_parser.py
index 8670e33..f75a430 100644
--- a/tests/test_todo_parser.py
+++ b/tests/test_todo_parser.py
@@ -231,19 +231,19 @@ class EscapeMarkdownTest(unittest.TestCase):
         self.assertEqual(issue.body[1], '\\<AnotherTag\\>')
 
 
-class CostumeLanguageTest(unittest.TestCase):
-    def test_costume_lang_load(self):
-        os.environ['INPUT_LANGUAGES'] = 'tests/costume_languages.json'
+class customLanguageTest(unittest.TestCase):
+    def test_custom_lang_load(self):
+        os.environ['INPUT_LANGUAGES'] = 'tests/custom_languages.json'
         parser = TodoParser()
-        # Test if the costume language ILS is actually loaded into the system
+        # Test if the custom language ILS is actually loaded into the system
         self.assertIsNotNone(parser.languages_dict['ILS'])
         self.assertEqual(self.count_syntax(parser, 'ILS'), 1)
 
-    def test_costume_lang_not_dupplicate(self):
-        os.environ['INPUT_LANGUAGES'] = 'tests/costume_languages.json'
+    def test_custom_lang_not_dupplicate(self):
+        os.environ['INPUT_LANGUAGES'] = 'tests/custom_languages.json'
         parser = TodoParser()
 
-        # Test if a costume language can overwrite the rules of an existing one
+        # Test if a custom language can overwrite the rules of an existing one
         self.assertEqual(self.count_syntax(parser, 'Java'), 1)
         for syntax in parser.syntax_dict:
             if syntax['language'] == 'Java':
@@ -258,7 +258,7 @@ class CostumeLanguageTest(unittest.TestCase):
         self.assertEqual(parser.languages_dict['Java']['extensions'][0], ".java2")
 
     def test_url_load(self):
-        os.environ['INPUT_LANGUAGES'] = 'https://raw.githubusercontent.com/alstr/todo-to-issue-action/blob/master/tests/costume_languages.json'
+        os.environ['INPUT_LANGUAGES'] = 'https://raw.githubusercontent.com/alstr/todo-to-issue-action/blob/master/tests/custom_languages.json'
         os.environ['INPUT_NO_STANDARD'] = 'true'
         parser = TodoParser()