diff --git a/resources/schema/monolingual_dictionaries.xsd b/resources/schema/monolingual_dictionaries.xsd
index 15949bd..f32e1e9 100644
--- a/resources/schema/monolingual_dictionaries.xsd
+++ b/resources/schema/monolingual_dictionaries.xsd
@@ -42,6 +42,7 @@
                               </xsd:sequence>
                               <xsd:attribute name="id" type="xsd:int"/>
                               <xsd:attribute name="key" type="xsd:string"/>
+                              <xsd:attribute name="dummy" type="xsd:boolean"/>
                             </xsd:complexType>
                           </xsd:element>
                         </xsd:sequence>