diff --git a/docs/markdown/Installing.md b/docs/markdown/Installing.md
index f18688902..3454d49b2 100644
--- a/docs/markdown/Installing.md
+++ b/docs/markdown/Installing.md
@@ -44,7 +44,7 @@ giving an absolute install path.
 install_data(sources : 'foo.dat', install_dir : '/etc') # -> /etc/foo.dat
 ```
 
-## Custom install behaviour ##
+## Custom install behavior ##
 
 Sometimes you need to do more than just install basic targets. Meson makes this easy by allowing you to specify a custom script to execute at install time. As an example, here is a script that generates an empty file in a custom directory.
 
diff --git a/docs/markdown/Reference-manual.md b/docs/markdown/Reference-manual.md
index c9b9f131d..116fd58f4 100644
--- a/docs/markdown/Reference-manual.md
+++ b/docs/markdown/Reference-manual.md
@@ -83,7 +83,7 @@ Note that all these options are also available while running the `mesontest` scr
     void benchmark(name, executable, ...)
 ```
 
-Creates a benchmark item that will be run when the benchmark target is run. The behaviour of this function is identical to `test` with the exception that there is no `is_parallel` keyword, because benchmarks are never run in parallel.
+Creates a benchmark item that will be run when the benchmark target is run. The behavior of this function is identical to `test` with the exception that there is no `is_parallel` keyword, because benchmarks are never run in parallel.
 
 ### build_target()
 
@@ -152,7 +152,7 @@ Create a custom top level build target. The only positional argument is the name
 The list of strings passed to the `command` keyword argument accept the following special string substitutions:
 
 - `@INPUT@` the full path to the input passed to `input`. If more than one input is specified, all of them will be substituted as separate arguments only if the command uses `'@INPUT@'` as a standalone-argument. For instance, this would not work: `command : ['cp', './@INPUT@']`, but this would: `command : ['cp', '@INPUT@']`.
-- `@OUTPUT@` the full path to the output passed to `output`. If more than one outputs are specified, the behaviour is the same as `@INPUT@`.
+- `@OUTPUT@` the full path to the output passed to `output`. If more than one outputs are specified, the behavior is the same as `@INPUT@`.
 - `@INPUT0@` `@INPUT1@` `...` the full path to the input with the specified array index in `input`
 - `@OUTPUT0@` `@OUTPUT1@` `...` the full path to the output with the specified array index in `output`
 - `@OUTDIR@` the full path to the directory where the output(s) must be written
@@ -224,7 +224,7 @@ Creates a new executable. The first argument specifies its name and the remainin
 
 These input files can be sources, objects, libraries, or any other file. Meson will automatically categorize them based on the extension and use them accordingly. For instance, sources (`.c`, `.cpp`, `.vala`, `.rs`, etc) will be compiled, objects (`.o`, `.obj`) and libraries (`.so`, `.dll`, etc) will be linked, and all other files (headers, unknown extensions, etc) will be ignored.
 
-With the Ninja backend, Meson will create a build-time [order-only dependency](https://ninja-build.org/manual.html#ref_dependencies) on all generated input files, including unknown files. For all input files (generated and non-generated), Meson uses the [dependency file](https://ninja-build.org/manual.html#ref_headers) generated by your compiler to determine when to rebuild sources. The behaviour is similar for other backends.
+With the Ninja backend, Meson will create a build-time [order-only dependency](https://ninja-build.org/manual.html#ref_dependencies) on all generated input files, including unknown files. For all input files (generated and non-generated), Meson uses the [dependency file](https://ninja-build.org/manual.html#ref_headers) generated by your compiler to determine when to rebuild sources. The behavior is similar for other backends.
 
 Executable supports the following keyword arguments. Note that just like the positional arguments above, these keyword arguments can also be passed to [shared and static libraries](#library).
 
@@ -458,7 +458,7 @@ Installs the specified man files from the source tree into system's man director
     void install_subdir(subdir_name)
 ```
 
-Installs the entire given subdirectory and its contents from the source tree to the location specified by the keyword argument `install_dir`. Note that due to implementation issues this command deletes the entire target dir before copying the files, so you should never use `install_subdir` to install into two overlapping directories (such as `foo` and `foo/bar`) because if you do the behaviour is undefined.
+Installs the entire given subdirectory and its contents from the source tree to the location specified by the keyword argument `install_dir`. Note that due to implementation issues this command deletes the entire target dir before copying the files, so you should never use `install_subdir` to install into two overlapping directories (such as `foo` and `foo/bar`) because if you do the behavior is undefined.
 
 ### is_variable()
 
@@ -641,7 +641,7 @@ This command detects revision control commit information at build time and place
 - `output` file to write the results to (e.g. `version.c`)
 - `fallback` version number to use when no revision control information is present, such as when building from a release tarball
 
-Meson will read the contents of `input`, replace the string `@VCS_TAG@` with the detected revision number and write the result to `output`. This method returns an opaque [`custom_target`](#custom_target) object that you should put in your main program. If you desire more specific behaviour than what this command provides, you should use `custom_target`.
+Meson will read the contents of `input`, replace the string `@VCS_TAG@` with the detected revision number and write the result to `output`. This method returns an opaque [`custom_target`](#custom_target) object that you should put in your main program. If you desire more specific behavior than what this command provides, you should use `custom_target`.
 
 ## Built-in objects
 
diff --git a/docs/markdown/Release-notes-for-0.40.0.md b/docs/markdown/Release-notes-for-0.40.0.md
index 1aa668f42..a480788a8 100644
--- a/docs/markdown/Release-notes-for-0.40.0.md
+++ b/docs/markdown/Release-notes-for-0.40.0.md
@@ -87,7 +87,7 @@ qt5_dep = dependency('qt5', modules : 'core', method : 'qmake')
 
 ## Link whole contents of static libraries
 
-The default behaviour of static libraries is to discard all symbols that are not not directly referenced. This may lead to exported symbols being lost. Most compilers support "whole archive" linking that includes all symbols and code of a given static library. This is exposed with the `link_whole` keyword.
+The default behavior of static libraries is to discard all symbols that are not not directly referenced. This may lead to exported symbols being lost. Most compilers support "whole archive" linking that includes all symbols and code of a given static library. This is exposed with the `link_whole` keyword.
 
 ```meson
 shared_library('foo', 'foo.c', link_whole : some_static_library)
diff --git a/docs/markdown/Unit-tests.md b/docs/markdown/Unit-tests.md
index b94cd8405..1aa78065b 100644
--- a/docs/markdown/Unit-tests.md
+++ b/docs/markdown/Unit-tests.md
@@ -53,7 +53,7 @@ $ MESON_TESTTHREADS=5 ninja test
 
 ## Skipped tests
 
-Sometimes a test can only determine at runtime that it can not be run. The GNU standard approach in this case is to exit the program with error code 77. Meson will detect this and report these tests as skipped rather than failed. This behaviour was added in version 0.37.0.
+Sometimes a test can only determine at runtime that it can not be run. The GNU standard approach in this case is to exit the program with error code 77. Meson will detect this and report these tests as skipped rather than failed. This behavior was added in version 0.37.0.
 
 ## Testing tool
 
diff --git a/docs/markdown/howtox.md b/docs/markdown/howtox.md
index 2e43276c1..bc8333255 100644
--- a/docs/markdown/howtox.md
+++ b/docs/markdown/howtox.md
@@ -28,7 +28,7 @@ executable(..., dependencies : thread_dep)
 
 ## Set extra compiler and linker flags from the outside (when e.g. building distro packages)
 
-The behaviour is the same as with other build systems, with environment variables during first invocation.
+The behavior is the same as with other build systems, with environment variables during first invocation.
 
 ```console
 $ CFLAGS=-fsomething LDFLAGS=-Wl,--linker-flag meson <options>
diff --git a/mesonbuild/backend/ninjabackend.py b/mesonbuild/backend/ninjabackend.py
index fd6489c6d..88bd7ca2e 100644
--- a/mesonbuild/backend/ninjabackend.py
+++ b/mesonbuild/backend/ninjabackend.py
@@ -2375,7 +2375,7 @@ rule FORTRAN_DEP_HACK
             cmds.append('-D' + k + '=' + (v.value if isinstance(v.value, str) else str(v.value).lower()))
         # The order of these arguments must be the same between runs of Meson
         # to ensure reproducible output. The order we pass them shouldn't
-        # affect behaviour in any other way.
+        # affect behavior in any other way.
         return sorted(cmds)
 
     # For things like scan-build and other helper tools we might have.
diff --git a/mesonbuild/compilers.py b/mesonbuild/compilers.py
index ba0fb4e9a..3d2cd9613 100644
--- a/mesonbuild/compilers.py
+++ b/mesonbuild/compilers.py
@@ -761,7 +761,7 @@ class CCompiler(Compiler):
     def split_shlib_to_parts(self, fname):
         return None, fname
 
-    # The default behaviour is this, override in
+    # The default behavior is this, override in
     # OSX and MSVC.
     def build_rpath_args(self, build_dir, rpath_paths, install_rpath):
         return build_unix_rpath_args(build_dir, rpath_paths, install_rpath)
diff --git a/mesonbuild/scripts/depfixer.py b/mesonbuild/scripts/depfixer.py
index fa76a9541..2de50ba60 100644
--- a/mesonbuild/scripts/depfixer.py
+++ b/mesonbuild/scripts/depfixer.py
@@ -303,7 +303,7 @@ class Elf(DataSizes):
         # completely unrelated. This has already happened once with X.org.
         # Thus we want to keep this change as small as possible to minimize
         # the chance of obliterating other strings. It might still happen
-        # but our behaviour is identical to what chrpath does and it has
+        # but our behavior is identical to what chrpath does and it has
         # been in use for ages so based on that this should be rare.
         if not new_rpath:
             self.remove_rpath_entry(entrynum)
diff --git a/run_unittests.py b/run_unittests.py
index 1d80aaca7..d285e6a53 100755
--- a/run_unittests.py
+++ b/run_unittests.py
@@ -1246,7 +1246,7 @@ class LinuxlikeTests(BasePlatformTests):
                 raise unittest.SkipTest('QMake not found')
             # For some inexplicable reason qmake --version gives different
             # results when run from the command line vs invoked by Python.
-            # Check for both cases in case this behaviour changes in the future.
+            # Check for both cases in case this behavior changes in the future.
             output = subprocess.getoutput(['qmake', '--version'])
             if 'Qt version 5' not in output and 'qt5' not in output:
                 raise unittest.SkipTest('Qmake found, but it is not for Qt 5.')