diff --git a/fast_autocomplete/dwg.py b/fast_autocomplete/dwg.py
index 9c0f7e0..fda3669 100644
--- a/fast_autocomplete/dwg.py
+++ b/fast_autocomplete/dwg.py
@@ -201,7 +201,12 @@ def insert_word_branch(self, word, leaf_node=None, add_word=True, original_key=N
                 count=count,
                 insert_count=self.SHOULD_INCLUDE_COUNT
             )
-            temp_leaf_node.children[word[-1]] = leaf_node
+            # It already has children
+            if temp_leaf_node.children and word[-1] in temp_leaf_node.children:
+                temp_leaf_node.children[word[-1]].word = leaf_node.word
+            # otherwise merge into the leaf node
+            else:
+                temp_leaf_node.children[word[-1]] = leaf_node
         else:
             leaf_node = self._dwg.insert(
                 word,
diff --git a/tests/test_autocomplete.py b/tests/test_autocomplete.py
index 7943198..88e068c 100644
--- a/tests/test_autocomplete.py
+++ b/tests/test_autocomplete.py
@@ -101,6 +101,13 @@ def test_search_unicode_without_synonyms(self, word, max_cost, size, expected_re
         print_results(locals())
         assert expected_results == results
 
+    def test_autocomplete_synonym_part_of_another_word(self):
+        words = {'cartoon': {}, 'vehicle': {}}
+        synonyms = {'vehicle': ['car']}
+        autocomplete = AutoComplete(words=words, synonyms=synonyms)
+        result = autocomplete.search(word='ca')
+        assert [['vehicle'], ['cartoon']] == result
+
 
 STEP_DESCENDANTS_ONLY = [FindStep.descendants_only]
 STEP_FUZZY_FOUND = [FindStep.fuzzy_try, FindStep.fuzzy_found]