diff --git a/Include/odictobject.h b/Include/odictobject.h
--- a/Include/odictobject.h
+++ b/Include/odictobject.h
@@ -28,6 +28,8 @@
 PyAPI_FUNC(int) PyODict_SetItem(PyObject *od, PyObject *key, PyObject *item);
 PyAPI_FUNC(int) PyODict_DelItem(PyObject *od, PyObject *key);
 
+PyAPI_FUNC(PyObject *) _PyODict_KeysAsList(PyObject *od);
+
 /* wrappers around PyDict* functions */
 #define PyODict_GetItem(od, key) PyDict_GetItem((PyObject *)od, key)
 #define PyODict_Contains(od, key) PyDict_Contains((PyObject *)od, key)
diff --git a/Lib/test/test_metaclass.py b/Lib/test/test_metaclass.py
--- a/Lib/test/test_metaclass.py
+++ b/Lib/test/test_metaclass.py
@@ -180,7 +180,7 @@
     meta: C ()
     ns: [('__module__', 'test.test_metaclass'), ('__qualname__', 'C'), ('a', 42), ('b', 24)]
     kw: []
-    >>> type(C) is dict
+    >>> type(C) is OrderedDict
     True
     >>> print(sorted(C.items()))
     [('__module__', 'test.test_metaclass'), ('__qualname__', 'C'), ('a', 42), ('b', 24)]
@@ -212,7 +212,7 @@
 The default metaclass must define a __prepare__() method.
 
     >>> type.__prepare__()
-    {}
+    OrderedDict()
     >>>
 
 Make sure it works with subclassing.
@@ -248,6 +248,7 @@
 
 """
 
+from collections import OrderedDict
 import sys
 
 # Trace function introduces __locals__ which causes various tests to fail.
diff --git a/Objects/odictobject.c b/Objects/odictobject.c
--- a/Objects/odictobject.c
+++ b/Objects/odictobject.c
@@ -1770,6 +1770,21 @@
     return res;
 };
 
+PyObject *
+_PyODict_KeysAsList(PyObject *od) {
+//    return PyObject_CallFunctionObjArgs((PyObject *)&PyList_Type, od, NULL);
+    Py_ssize_t i = 0;
+    _ODictNode *node;
+    PyObject *keys = PyList_New(PyODict_Size(od));
+    if (keys == NULL)
+        return NULL;
+    _odict_FOREACH((PyODictObject *)od, node) {
+        Py_INCREF(_odictnode_KEY(node));
+        PyList_SET_ITEM(keys, i, _odictnode_KEY(node));
+        i++;
+    }
+    return keys;
+}
 
 /* -------------------------------------------
  * The OrderedDict views (keys/values/items)
diff --git a/Objects/typeobject.c b/Objects/typeobject.c
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -2310,6 +2310,7 @@
         }
     }
 
+    /* XXX Does PyDict_Type have to be exact? */
     /* Check arguments: (name, bases, dict) */
     if (!PyArg_ParseTupleAndKeywords(args, kwds, "UO!O!:type", kwlist,
                                      &name,
@@ -2352,10 +2353,24 @@
         goto error;
     }
 
+    /* Copy the definition namespace into a new dict. */
+    /* XXX Is OrderedDict compatible with the split-keys mechanism? */
     dict = PyDict_Copy(orig_dict);
     if (dict == NULL)
         goto error;
 
+    /* Record the definition order of the class's namespace. */
+    if (PyODict_Check(orig_dict)) {
+        int res;
+        PyObject *names = _PyODict_KeysAsList(orig_dict);
+        if (names == NULL)
+            goto error;
+        res = PyDict_SetItemString(dict, "__definition_order__", names);
+        Py_DECREF(names);
+        if (res != 0)
+            goto error;
+    }
+
     /* Check for a __slots__ sequence variable in dict, and count it */
     slots = _PyDict_GetItemId(dict, &PyId___slots__);
     nslots = 0;
@@ -3085,7 +3100,7 @@
 static PyObject *
 type_prepare(PyObject *self, PyObject *args, PyObject *kwds)
 {
-    return PyDict_New();
+    return PyODict_New();
 }
 
 /*
diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c
--- a/Python/bltinmodule.c
+++ b/Python/bltinmodule.c
@@ -145,7 +145,7 @@
     if (prep == NULL) {
         if (PyErr_ExceptionMatches(PyExc_AttributeError)) {
             PyErr_Clear();
-            ns = PyDict_New();
+            ns = PyODict_New();
         }
         else {
             Py_DECREF(meta);