diff --git a/lib/geocoder/results/nominatim.rb b/lib/geocoder/results/nominatim.rb
index 0826754cb0313a8bd81b308fd235436965e196e6..1235bd7d9a8b4ae73445a658a445709b269f81e6 100644
--- a/lib/geocoder/results/nominatim.rb
+++ b/lib/geocoder/results/nominatim.rb
@@ -79,7 +79,7 @@ module Geocoder::Result
          polygonpoints display_name class type stadium]
     end
 
-    define_method 'class' do
+    def class
       warn "DEPRECATION WARNING: The 'class' method of Geocoder::Result::Nominatim objects is deprecated and will be removed in Geocoder version 1.2.0. Please use 'place_class' instead."
       @data['class']
     end