diff --git a/Objects/stringobject.c b/Objects/stringobject.c
index ac4ad04..0425b1b 100644
--- a/Objects/stringobject.c
+++ b/Objects/stringobject.c
@@ -1770,12 +1770,12 @@
 
 
 PyDoc_STRVAR(strip__doc__,
-"S.strip([sep]) -> string or unicode\n\
+"S.strip([chars]) -> string or unicode\n\
 \n\
 Return a copy of the string S with leading and trailing\n\
 whitespace removed.\n\
-If sep is given and not None, remove characters in sep instead.\n\
-If sep is unicode, S will be converted to unicode before stripping");
+If chars is given and not None, remove characters in chars instead.\n\
+If chars is unicode, S will be converted to unicode before stripping");
 
 static PyObject *
 string_strip(PyStringObject *self, PyObject *args)
@@ -1788,11 +1788,11 @@
 
 
 PyDoc_STRVAR(lstrip__doc__,
-"S.lstrip([sep]) -> string or unicode\n\
+"S.lstrip([chars]) -> string or unicode\n\
 \n\
 Return a copy of the string S with leading whitespace removed.\n\
-If sep is given and not None, remove characters in sep instead.\n\
-If sep is unicode, S will be converted to unicode before stripping");
+If chars is given and not None, remove characters in chars instead.\n\
+If chars is unicode, S will be converted to unicode before stripping");
 
 static PyObject *
 string_lstrip(PyStringObject *self, PyObject *args)
@@ -1805,11 +1805,11 @@
 
 
 PyDoc_STRVAR(rstrip__doc__,
-"S.rstrip([sep]) -> string or unicode\n\
+"S.rstrip([chars]) -> string or unicode\n\
 \n\
 Return a copy of the string S with trailing whitespace removed.\n\
-If sep is given and not None, remove characters in sep instead.\n\
-If sep is unicode, S will be converted to unicode before stripping");
+If chars is given and not None, remove characters in chars instead.\n\
+If chars is unicode, S will be converted to unicode before stripping");
 
 static PyObject *
 string_rstrip(PyStringObject *self, PyObject *args)
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index 847580c..096dfcb 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -5247,12 +5247,12 @@
 
 
 PyDoc_STRVAR(strip__doc__,
-"S.strip([sep]) -> unicode\n\
+"S.strip([chars]) -> unicode\n\
 \n\
 Return a copy of the string S with leading and trailing\n\
 whitespace removed.\n\
-If sep is given and not None, remove characters in sep instead.\n\
-If sep is a str, it will be converted to unicode before stripping");
+If chars is given and not None, remove characters in chars instead.\n\
+If chars is a str, it will be converted to unicode before stripping");
 
 static PyObject *
 unicode_strip(PyUnicodeObject *self, PyObject *args)
@@ -5265,11 +5265,11 @@
 
 
 PyDoc_STRVAR(lstrip__doc__,
-"S.lstrip([sep]) -> unicode\n\
+"S.lstrip([chars]) -> unicode\n\
 \n\
 Return a copy of the string S with leading whitespace removed.\n\
-If sep is given and not None, remove characters in sep instead.\n\
-If sep is a str, it will be converted to unicode before stripping");
+If chars is given and not None, remove characters in chars instead.\n\
+If chars is a str, it will be converted to unicode before stripping");
 
 static PyObject *
 unicode_lstrip(PyUnicodeObject *self, PyObject *args)
@@ -5282,11 +5282,11 @@
 
 
 PyDoc_STRVAR(rstrip__doc__,
-"S.rstrip([sep]) -> unicode\n\
+"S.rstrip([chars]) -> unicode\n\
 \n\
 Return a copy of the string S with trailing whitespace removed.\n\
-If sep is given and not None, remove characters in sep instead.\n\
-If sep is a str, it will be converted to unicode before stripping");
+If chars is given and not None, remove characters in chars instead.\n\
+If chars is a str, it will be converted to unicode before stripping");
 
 static PyObject *
 unicode_rstrip(PyUnicodeObject *self, PyObject *args)