diff --git a/ety/word.py b/ety/word.py
index ac745b6..d886ff5 100644
--- a/ety/word.py
+++ b/ety/word.py
@@ -21,8 +21,7 @@ def __init__(self, word, language='eng', is_source=False):
             'direct': [],
             'recursive': []
         }
-        self._id = u"{}:{}".format(
-            self.word.lower(), self.language.iso.lower())
+        self._id = u"{}:{}".format(self.word, self.language.iso)
 
     def origins(self, recursive=False):
         search = 'recursive' if recursive else 'direct'
@@ -33,10 +32,8 @@ def origins(self, recursive=False):
             return o
 
         row = list(filter(
-            lambda entry: (
-                entry['a_word'].lower() == self.word.lower()
-                and entry['a_lang'].lower() == self.language.iso.lower()),
-            etymwn_data))
+            lambda entry: entry['a_word'] == self.word and entry[
+                'a_lang'] == self.language.iso, etymwn_data))
 
         o = [Word(item['b_word'], item['b_lang']) for item in row]
 
diff --git a/tests.py b/tests.py
index ec9b1fd..956ce8e 100644
--- a/tests.py
+++ b/tests.py
@@ -98,18 +98,6 @@ def test_census_origins(self):
 
         self.assertEqual(d.origins(recursive=True), e + f)
 
-    def test_origins_allows_any_case(self):
-        wonky_word_origins = ety.origins("tEsT")
-        lower_word_origins = ety.origins("test")
-
-        self.assertEqual(wonky_word_origins, lower_word_origins)
-
-    def test_tree_allows_any_case(self):
-        wonky_word_tree = [node.data for node in ety.tree("tEsT").all_nodes()]
-        lower_word_tree = [node.data for node in ety.tree("test").all_nodes()]
-
-        self.assertEqual(wonky_word_tree, lower_word_tree)
-
     @stdout_capture
     def test_cli_no_args(self, output):
         words = ["test"]