diff --git a/build_configs/darwin_macports.txt b/build_configs/darwin_macports.txt
index 821e0c792aa36718fa7e773f82be8b0b8156b4df..5d5aefe2dd738d0a2b6f9f6370b82d95bf8e4bff 100644
--- a/build_configs/darwin_macports.txt
+++ b/build_configs/darwin_macports.txt
@@ -1,4 +1,4 @@
-# this file contains a list of settings to be used on MacOS X with
+# this file contains a list of settings to be used on macOS with
# the dependencies installed over MacPorts
set(BOOST_ROOT "/opt/local" CACHE PATH "prefix for the boost")
set(PYTHON_ROOT "/opt/local" CACHE PATH "prefix for python")
diff --git a/cmake_support/FindPython.cmake b/cmake_support/FindPython.cmake
index e1ba2b78830213e3696b602693c42d2dfa228dff..673a802199b94de7b43a08b38a549eec275ae85e 100644
--- a/cmake_support/FindPython.cmake
+++ b/cmake_support/FindPython.cmake
@@ -2,7 +2,7 @@
# Check for Python Libraries
#
# PYTHON_IGNORE_FRAMEWORKS if set, do not check for python frameworks.
-# has meaning on MacOS X only
+# has meaning on macOS only
# PYTHON_ROOT Prefix for python libraries
# PYTHON_MIN_VERSION minimal python version required
#
diff --git a/deployment/macos/pack.py b/deployment/macos/pack.py
index d849446be5d0f2e01d2ff27bed4c958cf5e7d16d..beb7d7d74932339475945cee35ccc59048e9f5e1 100644
--- a/deployment/macos/pack.py
+++ b/deployment/macos/pack.py
@@ -1,7 +1,7 @@
"""
deploy.py helps you package your code into a standalone application.
-for now, MacOS X and Linux are supported...
+for now, macOS and Linux are supported...
"""
import os
import subprocess
diff --git a/modules/doc/install.rst b/modules/doc/install.rst
index 1caff8a664a9fc8bdd8f0ab9c1ce463e586c8b1c..8bb1f03db2742cc4375bca6f5b3b688f0dc1c1cb 100644
--- a/modules/doc/install.rst
+++ b/modules/doc/install.rst
@@ -122,7 +122,7 @@ to CMake with via `-D<opt>=<value>`.
Flag to choose build generator
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-CMake supports different build generators. On UNIX, i.e. MacOS X and Linux, the
+CMake supports different build generators. On UNIX, i.e. macOS and Linux, the
default build generator is Makefiles, but it is also possible to use other
programs. For a list of supported build generators on your platform, start cmake
without parameters.
@@ -339,7 +339,7 @@ to run multiple jobs at once.
What's next?
--------------------------------------------------------------------------------
-On Linux and MacOS X, you can start dng from the command-line. The binaries are all located in stage/bin:
+On Linux and macOS, you can start dng from the command-line. The binaries are all located in stage/bin:
.. code-block:: bash
diff --git a/modules/doc/intro.rst b/modules/doc/intro.rst
index 457d995cfcc19341227e75a1eedfd9a7883377b9..25abc3c3dad1412718e0aed499abe9bf2305416a 100644
--- a/modules/doc/intro.rst
+++ b/modules/doc/intro.rst
@@ -30,7 +30,7 @@ The files we will be using in the tutorial are available in the examples
directory that comes with OpenStructure. Depending on your platform, the
examples are located at a different location:
- * on *MacOS X* the files are located inside the application bundle (DNG.app).
+ * on *macOS* the files are located inside the application bundle (DNG.app).
The file browser will automatically point to the examples.
* on *Linux* the files are located at PREFIX/share/openstructure/examples,
where PREFIX is the path to the directory containing OpenStructure.
@@ -41,7 +41,7 @@ Starting DNG
The graphical user interface of OpenStructure is called DNG (Dino/DeepView Next
Generation). To start it,
- * on *MacOS X* double click DNG.app
+ * on *macOS* double click DNG.app
* on *Linux* fire up a terminal change into the OpenStructure installation
directory and type 'bin/dng'. If you have the binary directory in the PATH,
typing *dng* is sufficient.
diff --git a/modules/doc/newmodule.rst b/modules/doc/newmodule.rst
index 8c4864cb4e0145f4ce8916f1384e7a92bf13f391..f4d86014ea2db36132d1bca2fff7202cb55b1ddb 100644
--- a/modules/doc/newmodule.rst
+++ b/modules/doc/newmodule.rst
@@ -117,7 +117,7 @@ The line containing the `DEPENDS_ON` directive lists all the modules on which
the new module depends (in this case :mod:`mol` and :mod:`ost.mol.alg`). The
`module` macro will take care of staging the headers, in this case into
`ost/mod` and compiling, linking and staging of a library with the name
-`libost_mod.so` (`libost_gmod.dylib` on MacOS X).
+`libost_mod.so` (`libost_gmod.dylib` on macOS).
.. note::
diff --git a/modules/gfx/src/glext_include.hh b/modules/gfx/src/glext_include.hh
index 4bc9decaed531cfd3cb87a8ab91e6612ab70bcd4..874b70a31137e6839574c48f712e7ec4978bb7fb 100644
--- a/modules/gfx/src/glext_include.hh
+++ b/modules/gfx/src/glext_include.hh
@@ -43,7 +43,7 @@
#include <ost/gfx/gl_include.hh>
#if defined(__APPLE__)
-// On all MacOS X version we support, OpenGL 2.0 is available, so it's safe to
+// On all macOS version we support, OpenGL 2.0 is available, so it's safe to
// hardcode the value here...
//same for windows vista and above, XP only has 1.1
#define OST_GL_VERSION_2_0 1
diff --git a/modules/gui/doc/tools.rst b/modules/gui/doc/tools.rst
index 8b4d6eaee4c1e9316f113b0da1118e6eeddd4054..87c6097213c483827604ce69a20ea48c316ac0de 100644
--- a/modules/gui/doc/tools.rst
+++ b/modules/gui/doc/tools.rst
@@ -25,7 +25,7 @@ The example `Write a Tool in Python` demonstrates how to add a simple tool
input_events Input Events
- Tools receive input events when the Control key (Command on MacOS X) is
+ Tools receive input events when the Control key (Command on macOS) is
pressed. This includes both keyboard events and mouse events such as mouse
move events, clicks and Real clicks.
diff --git a/modules/gui/pymod/__init__.py b/modules/gui/pymod/__init__.py
index da9be0da86b6fd27ddb5b6a539276f60635e8e5d..da6b1599a0b8378ba6153054c1ce72d0ca5f1581 100644
--- a/modules/gui/pymod/__init__.py
+++ b/modules/gui/pymod/__init__.py
@@ -111,7 +111,7 @@ def AddMenuAction(*args, **kwargs):
AddMenuAction('Scene', 'Background Color', SetBackgroundColor,
shortcut='Ctrl+B')
- Whenever you press Ctrl+B (Cmd+B on MacOS X), the action will be executed.
+ Whenever you press Ctrl+B (Cmd+B on macOS), the action will be executed.
Very often menu actions are coupled to the current selected objects in the
scene menu. These menu actions are either enabled or disabled depending on the
diff --git a/modules/gui/src/tools/tool.hh b/modules/gui/src/tools/tool.hh
index 3d79931cbddde29657a9d9f181b5392d9a302029..945855cca912d657573e8a1d236da68712e26cdc 100644
--- a/modules/gui/src/tools/tool.hh
+++ b/modules/gui/src/tools/tool.hh
@@ -47,7 +47,7 @@ class GLCanvas;
///
/// \section input_events Input Events
///
-/// Tools receive input events when the Control key (Command on MacOS X) is
+/// Tools receive input events when the Control key (Command on macOS) is
/// pressed. This includes both keyboard events and mouse events such as mouse
/// move events, clicks and Real clicks.
///