diff --git a/lang/python310/Portfile b/lang/python310/Portfile
index 3f3f4312d28a9..67104a13ca2b8 100644
--- a/lang/python310/Portfile
+++ b/lang/python310/Portfile
@@ -239,6 +239,12 @@ variant lto description {enable Link-Time Optimization} {
     configure.args-append   --with-lto
 }
 
+# Fixes the return type of `ttyname_r`
+# See /~https://github.com/python/cpython/issues/127614
+platform darwin 8 {
+    configure.cflags-append -D__DARWIN_UNIX03=1
+}
+
 platform darwin {
     # Build failures on 10.9 and older
     if {${os.major} > 11} {
diff --git a/lang/python311/Portfile b/lang/python311/Portfile
index aaae55863df5f..fedf0ca6671eb 100644
--- a/lang/python311/Portfile
+++ b/lang/python311/Portfile
@@ -246,6 +246,12 @@ variant lto description {enable Link-Time Optimization} {
     configure.args-append   --with-lto
 }
 
+# Fixes the return type of `ttyname_r`
+# See /~https://github.com/python/cpython/issues/127614
+platform darwin 8 {
+    configure.cflags-append -D__DARWIN_UNIX03=1
+}
+
 platform darwin {
     # Build failures on 10.9 and older
     if {${os.major} > 11} {
diff --git a/lang/python312/Portfile b/lang/python312/Portfile
index 27cb79742d579..cca73f3ca84a9 100644
--- a/lang/python312/Portfile
+++ b/lang/python312/Portfile
@@ -231,6 +231,12 @@ variant lto description {enable Link-Time Optimization} {
     configure.args-append   --with-lto
 }
 
+# Fixes the return type of `ttyname_r`
+# See /~https://github.com/python/cpython/issues/127614
+platform darwin 8 {
+    configure.cflags-append -D__DARWIN_UNIX03=1
+}
+
 platform darwin {
     # Build failures on 10.9 and older
     if {${os.major} > 11} {
diff --git a/lang/python313/Portfile b/lang/python313/Portfile
index a092b7ec26678..393adf623d2b0 100644
--- a/lang/python313/Portfile
+++ b/lang/python313/Portfile
@@ -232,6 +232,12 @@ variant lto description {enable Link-Time Optimization} {
     configure.args-append   --with-lto
 }
 
+# Fixes the return type of `ttyname_r`
+# See /~https://github.com/python/cpython/issues/127614
+platform darwin 8 {
+    configure.cflags-append -D__DARWIN_UNIX03=1
+}
+
 platform darwin {
     # Build failures on 10.10 and older
     if {${os.major} > 11} {
diff --git a/lang/python314-devel/Portfile b/lang/python314-devel/Portfile
index b73cfa27d2d30..1e88dfdfc2f85 100644
--- a/lang/python314-devel/Portfile
+++ b/lang/python314-devel/Portfile
@@ -232,6 +232,12 @@ variant lto description {enable Link-Time Optimization} {
     configure.args-append   --with-lto
 }
 
+# Fixes the return type of `ttyname_r`
+# See /~https://github.com/python/cpython/issues/127614
+platform darwin 8 {
+    configure.cflags-append -D__DARWIN_UNIX03=1
+}
+
 platform darwin {
     # Build failures on 10.10 and older
     if {${os.major} > 11} {
diff --git a/lang/python39/Portfile b/lang/python39/Portfile
index 7778249beebdd..fc40a4f4fb5f4 100644
--- a/lang/python39/Portfile
+++ b/lang/python39/Portfile
@@ -242,6 +242,12 @@ variant lto description {enable Link-Time Optimization} {
     configure.args-append   --with-lto
 }
 
+# Fixes the return type of `ttyname_r`
+# See /~https://github.com/python/cpython/issues/127614
+platform darwin 8 {
+    configure.cflags-append -D__DARWIN_UNIX03=1
+}
+
 platform darwin {
     # Build failures on 10.9 and older
     if {${os.major} > 11} {