diff --git a/Doc/library/inspect.rst b/Doc/library/inspect.rst
index 0f54376..1f5e72e 100644
--- a/Doc/library/inspect.rst
+++ b/Doc/library/inspect.rst
@@ -204,18 +204,19 @@
 
 .. function:: isclass(object)
 
-   Return true if the object is a class.
+   Return true if the object is a class, whether built-in or created in Python
+   code.
 
 
 .. function:: ismethod(object)
 
-   Return true if the object is a method.
+   Return true if the object is a bound method written in Python.
 
 
 .. function:: isfunction(object)
 
-   Return true if the object is a Python function or unnamed (:term:`lambda`)
-   function.
+   Return true if the object is a Python function, which includes functions
+   created by a :term:`lambda` expression.
 
 
 .. function:: isgeneratorfunction(object)
@@ -245,13 +246,14 @@
 
 .. function:: isbuiltin(object)
 
-   Return true if the object is a built-in function.
+   Return true if the object is a built-in function or a bound built-in method.
 
 
 .. function:: isroutine(object)
 
    Return true if the object is a user-defined or built-in function or method.
 
+
 .. function:: isabstract(object)
 
    Return true if the object is an abstract base class.
@@ -259,8 +261,9 @@
 
 .. function:: ismethoddescriptor(object)
 
-   Return true if the object is a method descriptor, but not if :func:`ismethod`
-   or :func:`isclass` or :func:`isfunction` are true.
+   Return true if the object is a method descriptor, but not if
+   :func:`ismethod`, :func:`isclass`, :func:`isfunction` or :func:`isbuiltin`
+   are true.
 
    This, for example, is true of ``int.__add__``.  An object passing this test
    has a :attr:`__get__` attribute but not a :attr:`__set__` attribute, but