diff --git a/lib/mongoid/fields.rb b/lib/mongoid/fields.rb
index 21657c507a..fd2d93e489 100644
--- a/lib/mongoid/fields.rb
+++ b/lib/mongoid/fields.rb
@@ -12,6 +12,9 @@ module Mongoid
   module Fields
     extend ActiveSupport::Concern
 
+    # @deprecated Use Mongoid::Fields::FieldTypes.mapping instead
+    TYPE_MAPPINGS = ::Mongoid::Fields::FieldTypes::DEFAULT_MAPPING
+
     StringifiedSymbol = Mongoid::StringifiedSymbol
     Boolean = Mongoid::Boolean
 
diff --git a/lib/mongoid/fields/field_types.rb b/lib/mongoid/fields/field_types.rb
index f8ae682a8f..27f691ed7f 100644
--- a/lib/mongoid/fields/field_types.rb
+++ b/lib/mongoid/fields/field_types.rb
@@ -64,8 +64,6 @@ def define(type, klass)
 
         delegate :delete, to: :mapping
 
-        private
-
         # The memoized mapping of field type definitions to classes.
         #
         # @return [ ActiveSupport::HashWithIndifferentAccess<Symbol, Class> ] The memoized field mapping.
@@ -73,6 +71,8 @@ def mapping
           @mapping ||= DEFAULT_MAPPING.dup
         end
 
+        private
+
         # Handles fallback for case where mapping does not contain the
         # requested type.
         #
diff --git a/spec/mongoid/fields/field_types_spec.rb b/spec/mongoid/fields/field_types_spec.rb
index fde6256d6e..379ce06366 100644
--- a/spec/mongoid/fields/field_types_spec.rb
+++ b/spec/mongoid/fields/field_types_spec.rb
@@ -128,4 +128,21 @@
       expect(described_class::DEFAULT_MAPPING[:integer]).to eq Integer
     end
   end
+
+  describe '.mapping' do
+
+    it 'returns the default mapping by default' do
+      expect(described_class.mapping).to eq described_class::DEFAULT_MAPPING
+    end
+
+    it 'can add a type' do
+      described_class.define(:my_string, String)
+      expect(described_class.mapping[:my_string]).to eq(String)
+    end
+
+    it 'can delete a default type' do
+      described_class.delete(:integer)
+      expect(described_class.mapping).to_not have_key(:integer)
+    end
+  end
 end
diff --git a/spec/mongoid/fields_spec.rb b/spec/mongoid/fields_spec.rb
index 10af3ad545..a46884798a 100644
--- a/spec/mongoid/fields_spec.rb
+++ b/spec/mongoid/fields_spec.rb
@@ -1838,4 +1838,10 @@ def self.model_name
       end
     end
   end
+
+  describe '::TYPE_MAPPINGS' do
+    it 'returns the default mapping' do
+      expect(described_class::TYPE_MAPPINGS).to eq ::Mongoid::Fields::FieldTypes::DEFAULT_MAPPING
+    end
+  end
 end