diff --git a/app/validators/belongs_to_host_taxonomy_validator.rb b/app/validators/belongs_to_host_taxonomy_validator.rb
index b92270c03cd..4929463c22b 100644
--- a/app/validators/belongs_to_host_taxonomy_validator.rb
+++ b/app/validators/belongs_to_host_taxonomy_validator.rb
@@ -16,7 +16,7 @@ def validate_each(record, attribute, value)
 
     unless (attribute_taxonomy_ids & host_taxonomy_ids).any?
       attribute_name = attribute.to_s.end_with?('_id') ? attribute : "#{attribute}_id"
-      record.errors.add(attribute_name, _("is not defined for host's %s") % _(taxonomy))
+      record.errors.add(attribute_name, _("is not defined for host's %s") % _(taxonomy.to_s))
     end
   end
 end