diff --git a/src/testdir/test_cmdline.vim b/src/testdir/test_cmdline.vim
index c4b7b57..9b2fee3 100644
--- a/src/testdir/test_cmdline.vim
+++ b/src/testdir/test_cmdline.vim
@@ -4267,7 +4267,7 @@
   " required for :*
   set cpo+=*
   let list = filter(getcompletion('', 'command'), 'exists(":" . v:val) == 0')
-  " :++ and :-- are only valid in Vim9 Script context, so they can be ignored
+  " :++ and :-- are only valid in Vim9 script context, so they can be ignored
   call assert_equal(['++', '--'], sort(list))
   call assert_equal(2, exists(':k'))
   call assert_equal(0, exists(':ke'))
diff --git a/src/testdir/test_source.vim b/src/testdir/test_source.vim
index 3692eee..55b2fff 100644
--- a/src/testdir/test_source.vim
+++ b/src/testdir/test_source.vim
@@ -57,7 +57,7 @@
   call assert_fails('source XtwoScript', 'E121:')
 endfunc
 
-" When sourcing a vim script, shebang should be ignored.
+" When sourcing a Vim script, shebang should be ignored.
 func Test_source_ignore_shebang()
   call writefile(['#!./xyzabc', 'let g:val=369'], 'Xsisfile.vim', 'D')
   source Xsisfile.vim
@@ -408,7 +408,7 @@
   source
   call assert_equal(10, Xtestfunc())
 
-  " test for sourcing a vim9 script with line continuation
+  " test for sourcing a Vim9 script with line continuation
   %d _
   let lines =<< trim END
      vim9script
diff --git a/src/testdir/test_vim9_cmd.vim b/src/testdir/test_vim9_cmd.vim
index 5407662..d38e1c8 100644
--- a/src/testdir/test_vim9_cmd.vim
+++ b/src/testdir/test_vim9_cmd.vim
@@ -159,7 +159,7 @@
   v9.CheckScriptSuccess(lines)
   delfunc g:TheFunc
 
-  # vim9cmd execute(cmd) executes code in vim9 script context
+  # vim9cmd execute(cmd) executes code in Vim9 script context
   lines =<< trim END
     vim9cmd execute("g:vim9executetest = 'bar'")
     call assert_equal('bar', g:vim9executetest)
@@ -176,7 +176,7 @@
   unlet g:vim9executetest1
   unlet g:vim9executetest2
 
-  # legacy call execute(cmd) executes code in vim script context
+  # legacy call execute(cmd) executes code in Vim script context
   lines =<< trim END
     vim9script
     legacy call execute("let g:vim9executetest = 'bar'")
diff --git a/src/testdir/vim9.vim b/src/testdir/vim9.vim
index 64922b7..b994855 100644
--- a/src/testdir/vim9.vim
+++ b/src/testdir/vim9.vim
@@ -1,6 +1,6 @@
 vim9script
 
-# Utility functions for testing vim9 script
+# Utility functions for testing Vim9 script
 
 # Use a different file name for each run.
 var sequence = 1