diff --git a/Grammar/python.gram b/Grammar/python.gram
index 53288a5418c931..cb23dec73c9157 100644
--- a/Grammar/python.gram
+++ b/Grammar/python.gram
@@ -1259,7 +1259,7 @@ invalid_parameters:
     | (slash_no_default | slash_with_default) param_maybe_default* a='/' {
         RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "/ may appear only once") }
     | slash_no_default? param_no_default* invalid_parameters_helper a=param_no_default {
-        RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "parameter without a default follows parameter with a default") }
+        RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "positional parameter without a default follows parameter with a default") }
     | param_no_default* a='(' param_no_default+ ','? b=')' {
         RAISE_SYNTAX_ERROR_KNOWN_RANGE(a, b, "Function parameters cannot be parenthesized") }
     | (slash_no_default | slash_with_default)? param_maybe_default* '*' (',' | param_no_default) param_maybe_default* a='/' {
@@ -1287,7 +1287,7 @@ invalid_lambda_parameters:
     | (lambda_slash_no_default | lambda_slash_with_default) lambda_param_maybe_default* a='/' {
         RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "/ may appear only once") }
     | lambda_slash_no_default? lambda_param_no_default* invalid_lambda_parameters_helper a=lambda_param_no_default {
-        RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "parameter without a default follows parameter with a default") }
+        RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "positional parameter without a default follows parameter with a default") }
     | lambda_param_no_default* a='(' ','.lambda_param+ ','? b=')' {
         RAISE_SYNTAX_ERROR_KNOWN_RANGE(a, b, "Lambda expression parameters cannot be parenthesized") }
     | (lambda_slash_no_default | lambda_slash_with_default)? lambda_param_maybe_default* '*' (',' | lambda_param_no_default) lambda_param_maybe_default* a='/' {
diff --git a/Lib/test/test_positional_only_arg.py b/Lib/test/test_positional_only_arg.py
index eea0625012da6d..928a02c4230f31 100644
--- a/Lib/test/test_positional_only_arg.py
+++ b/Lib/test/test_positional_only_arg.py
@@ -24,11 +24,11 @@ def assertRaisesSyntaxError(self, codestr, regex="invalid syntax"):
             compile(codestr + "\n", "<test>", "single")
 
     def test_invalid_syntax_errors(self):
-        check_syntax_error(self, "def f(a, b = 5, /, c): pass", "parameter without a default follows parameter with a default")
-        check_syntax_error(self, "def f(a = 5, b, /, c): pass", "parameter without a default follows parameter with a default")
-        check_syntax_error(self, "def f(a = 5, b=1, /, c, *, d=2): pass", "parameter without a default follows parameter with a default")
-        check_syntax_error(self, "def f(a = 5, b, /): pass", "parameter without a default follows parameter with a default")
-        check_syntax_error(self, "def f(a, /, b = 5, c): pass", "parameter without a default follows parameter with a default")
+        check_syntax_error(self, "def f(a, b = 5, /, c): pass", "positional parameter without a default follows parameter with a default")
+        check_syntax_error(self, "def f(a = 5, b, /, c): pass", "positional parameter without a default follows parameter with a default")
+        check_syntax_error(self, "def f(a = 5, b=1, /, c, *, d=2): pass", "positional parameter without a default follows parameter with a default")
+        check_syntax_error(self, "def f(a = 5, b, /): pass", "positional parameter without a default follows parameter with a default")
+        check_syntax_error(self, "def f(a, /, b = 5, c): pass", "positional parameter without a default follows parameter with a default")
         check_syntax_error(self, "def f(*args, /): pass")
         check_syntax_error(self, "def f(*args, a, /): pass")
         check_syntax_error(self, "def f(**kwargs, /): pass")
@@ -46,11 +46,11 @@ def test_invalid_syntax_errors(self):
         check_syntax_error(self, "def f(a, *, c, /, d, e): pass")
 
     def test_invalid_syntax_errors_async(self):
-        check_syntax_error(self, "async def f(a, b = 5, /, c): pass", "parameter without a default follows parameter with a default")
-        check_syntax_error(self, "async def f(a = 5, b, /, c): pass", "parameter without a default follows parameter with a default")
-        check_syntax_error(self, "async def f(a = 5, b=1, /, c, d=2): pass", "parameter without a default follows parameter with a default")
-        check_syntax_error(self, "async def f(a = 5, b, /): pass", "parameter without a default follows parameter with a default")
-        check_syntax_error(self, "async def f(a, /, b = 5, c): pass", "parameter without a default follows parameter with a default")
+        check_syntax_error(self, "async def f(a, b = 5, /, c): pass", "positional parameter without a default follows parameter with a default")
+        check_syntax_error(self, "async def f(a = 5, b, /, c): pass", "positional parameter without a default follows parameter with a default")
+        check_syntax_error(self, "async def f(a = 5, b=1, /, c, d=2): pass", "positional parameter without a default follows parameter with a default")
+        check_syntax_error(self, "async def f(a = 5, b, /): pass", "positional parameter without a default follows parameter with a default")
+        check_syntax_error(self, "async def f(a, /, b = 5, c): pass", "positional parameter without a default follows parameter with a default")
         check_syntax_error(self, "async def f(*args, /): pass")
         check_syntax_error(self, "async def f(*args, a, /): pass")
         check_syntax_error(self, "async def f(**kwargs, /): pass")
@@ -234,11 +234,11 @@ def test_lambdas(self):
         self.assertEqual(x(1, 2), 3)
 
     def test_invalid_syntax_lambda(self):
-        check_syntax_error(self, "lambda a, b = 5, /, c: None", "parameter without a default follows parameter with a default")
-        check_syntax_error(self, "lambda a = 5, b, /, c: None", "parameter without a default follows parameter with a default")
-        check_syntax_error(self, "lambda a = 5, b=1, /, c, *, d=2: None", "parameter without a default follows parameter with a default")
-        check_syntax_error(self, "lambda a = 5, b, /: None", "parameter without a default follows parameter with a default")
-        check_syntax_error(self, "lambda a, /, b = 5, c: None", "parameter without a default follows parameter with a default")
+        check_syntax_error(self, "lambda a, b = 5, /, c: None", "positional parameter without a default follows parameter with a default")
+        check_syntax_error(self, "lambda a = 5, b, /, c: None", "positional parameter without a default follows parameter with a default")
+        check_syntax_error(self, "lambda a = 5, b=1, /, c, *, d=2: None", "positional parameter without a default follows parameter with a default")
+        check_syntax_error(self, "lambda a = 5, b, /: None", "positional parameter without a default follows parameter with a default")
+        check_syntax_error(self, "lambda a, /, b = 5, c: None", "positional parameter without a default follows parameter with a default")
         check_syntax_error(self, "lambda *args, /: None")
         check_syntax_error(self, "lambda *args, a, /: None")
         check_syntax_error(self, "lambda **kwargs, /: None")
diff --git a/Lib/test/test_syntax.py b/Lib/test/test_syntax.py
index 707d4fc6df16ea..a95b11dabc768e 100644
--- a/Lib/test/test_syntax.py
+++ b/Lib/test/test_syntax.py
@@ -394,12 +394,12 @@
 >>> def f(x, y=1, z):
 ...     pass
 Traceback (most recent call last):
-SyntaxError: parameter without a default follows parameter with a default
+SyntaxError: positional parameter without a default follows parameter with a default
 
 >>> def f(x, /, y=1, z):
 ...     pass
 Traceback (most recent call last):
-SyntaxError: parameter without a default follows parameter with a default
+SyntaxError: positional parameter without a default follows parameter with a default
 
 >>> def f(x, None):
 ...     pass
@@ -622,11 +622,11 @@
 
 >>> lambda a,d=3,c: None
 Traceback (most recent call last):
-SyntaxError: parameter without a default follows parameter with a default
+SyntaxError: positional parameter without a default follows parameter with a default
 
 >>> lambda a,/,d=3,c: None
 Traceback (most recent call last):
-SyntaxError: parameter without a default follows parameter with a default
+SyntaxError: positional parameter without a default follows parameter with a default
 
 >>> import ast; ast.parse('''
 ... def f(
diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2025-03-07-16-48-12.gh-issue-129545.t-9iTH.rst b/Misc/NEWS.d/next/Core_and_Builtins/2025-03-07-16-48-12.gh-issue-129545.t-9iTH.rst
new file mode 100644
index 00000000000000..b254ca2edb2279
--- /dev/null
+++ b/Misc/NEWS.d/next/Core_and_Builtins/2025-03-07-16-48-12.gh-issue-129545.t-9iTH.rst
@@ -0,0 +1,3 @@
+Change the text of the ``SyntaxError: parameter without a default follows parameter with a default``
+to ``SyntaxError: positional parameter without a default follows parameter with a default`` to improve
+error message clarity in certain cases.
diff --git a/Parser/parser.c b/Parser/parser.c
index edebddc95f968e..9cb0603f05666a 100644
--- a/Parser/parser.c
+++ b/Parser/parser.c
@@ -21487,7 +21487,7 @@ invalid_parameters_rule(Parser *p)
         )
         {
             D(fprintf(stderr, "%*c+ invalid_parameters[%d-%d]: %s succeeded!\n", p->level, ' ', _mark, p->mark, "slash_no_default? param_no_default* invalid_parameters_helper param_no_default"));
-            _res = RAISE_SYNTAX_ERROR_KNOWN_LOCATION ( a , "parameter without a default follows parameter with a default" );
+            _res = RAISE_SYNTAX_ERROR_KNOWN_LOCATION ( a , "positional parameter without a default follows parameter with a default" );
             if (_res == NULL && PyErr_Occurred()) {
                 p->error_indicator = 1;
                 p->level--;
@@ -22078,7 +22078,7 @@ invalid_lambda_parameters_rule(Parser *p)
         )
         {
             D(fprintf(stderr, "%*c+ invalid_lambda_parameters[%d-%d]: %s succeeded!\n", p->level, ' ', _mark, p->mark, "lambda_slash_no_default? lambda_param_no_default* invalid_lambda_parameters_helper lambda_param_no_default"));
-            _res = RAISE_SYNTAX_ERROR_KNOWN_LOCATION ( a , "parameter without a default follows parameter with a default" );
+            _res = RAISE_SYNTAX_ERROR_KNOWN_LOCATION ( a , "positional parameter without a default follows parameter with a default" );
             if (_res == NULL && PyErr_Occurred()) {
                 p->error_indicator = 1;
                 p->level--;