[DOC] refined "**" description in `Dir.glob` [ci skip]

As same as the description for `File.fnmatch`.
[Bug #17283]

1 files changed, 1 insertions, 1 deletions

diff --git a/dir.rb b/dir.rb
index 7eacc66fc7..f0636595f3 100644
--- a/dir.rb
+++ b/dir.rb
@@ -81,7 +81,7 @@ class Dir
   #   File::FNM_DOTMATCH flag or something like <code>"{*,.*}"</code>.
   #
   # <code>**</code>::
-  #   Matches directories recursively.
+  #   Matches directories recursively or files expansively.
   #
   # <code>?</code>::
   #   Matches any one character. Equivalent to <code>/.{1}/</code> in regexp.