Fix typos in docs

docs/src/reference/extension_types.rst

@@ -306,7 +306,7 @@ Depending on the application, one way or the other may be better:
   +-----+-----+-------+
 
   The named constants can be cimported from the ``cpython.object`` module.
-  They should generally be preferred over plain integers to improve readabilty.
+  They should generally be preferred over plain integers to improve readability.
 
 
 The ``__next__()`` Method

docs/src/tutorial/cdef_classes.rst

@@ -47,7 +47,7 @@ fast for use from Cython and one slower for use from Python. Then::
           return sin(x**2)
 
 This does slightly more than providing a python wrapper for a cdef
-method: unlike a cdef method, a cpdef method is fully overrideable by
+method: unlike a cdef method, a cpdef method is fully overridable by
 methods and instance attributes in Python subclasses.  It adds a
 little calling overhead compared to a cdef method.