diff --git a/mrbgems/mruby-rational/mrblib/rational.rb b/mrbgems/mruby-rational/mrblib/rational.rb
index febabbae7..aaafc9899 100644
--- a/mrbgems/mruby-rational/mrblib/rational.rb
+++ b/mrbgems/mruby-rational/mrblib/rational.rb
@@ -47,6 +47,8 @@ class Rational < Numeric
     end
   end
 
+  alias quo /
+
   def <=>(rhs)
     case rhs
     when Integer, Float