diff --git a/.github/MAINTAINERS b/.github/MAINTAINERS
index 7a080f936d..c316849cfb 100644
--- a/.github/MAINTAINERS
+++ b/.github/MAINTAINERS
@@ -225,6 +225,7 @@ runtime/ftplugin/liquid.vim		@tpope
 runtime/ftplugin/lua.vim		@dkearns
 runtime/ftplugin/lc.vim			@ribru17
 runtime/ftplugin/lynx.vim		@dkearns
+runtime/ftplugin/m17ndb.vim		@dseomn
 runtime/ftplugin/m3build.vim		@dkearns
 runtime/ftplugin/m3quake.vim		@dkearns
 runtime/ftplugin/markdown.vim		@tpope
@@ -367,6 +368,7 @@ runtime/indent/ld.vim			@dkearns
 runtime/indent/less.vim			@genoma
 runtime/indent/liquid.vim		@tpope
 runtime/indent/lua.vim			@marcuscf
+runtime/indent/m17ndb.vim		@dseomn
 runtime/indent/make.vim			@dkearns
 runtime/indent/meson.vim		@Liambeguin
 runtime/indent/mma.vim			@dkearns
@@ -533,6 +535,7 @@ runtime/syntax/liquid.vim		@tpope
 runtime/syntax/lua.vim			@marcuscf
 runtime/syntax/lyrics.vim		@ObserverOfTime
 runtime/syntax/lynx.vim			@dkearns
+runtime/syntax/m17ndb.vim		@dseomn
 runtime/syntax/m3build.vim		@dkearns
 runtime/syntax/m3quake.vim		@dkearns
 runtime/syntax/mailcap.vim		@dkearns
diff --git a/runtime/filetype.vim b/runtime/filetype.vim
index 0e669047e6..ff6905f913 100644
--- a/runtime/filetype.vim
+++ b/runtime/filetype.vim
@@ -1,7 +1,7 @@
 " Vim support file to detect file types
 "
 " Maintainer:	The Vim Project <https://github.com/vim/vim>
-" Last Change:	2025 Feb 22
+" Last Change:	2025 Feb 23
 " Former Maintainer:	Bram Moolenaar <Bram@vim.org>
 
 " Listen very carefully, I will say this only once
@@ -341,6 +341,11 @@ au BufNewFile,BufRead *.capnp			setf capnp
 " Cgdb config file
 au BufNewFile,BufRead cgdbrc			setf cgdbrc
 
+" m17n database files. */m17n/* matches installed files, */.m17n.d/* matches
+" per-user config files, */m17n-db/* matches the git repo. (must be before
+" *.cs)
+au BufNewFile,BufRead */{m17n,.m17n.d,m17n-db}/*.{ali,cs,dir,flt,fst,lnm,mic,mim,tbl} setf m17ndb
+
 " C#
 au BufNewFile,BufRead *.cs,*.csx,*.cake		setf cs
 
diff --git a/runtime/ftplugin/m17ndb.vim b/runtime/ftplugin/m17ndb.vim
new file mode 100644
index 0000000000..e4457cef9d
--- /dev/null
+++ b/runtime/ftplugin/m17ndb.vim
@@ -0,0 +1,17 @@
+" Vim filetype plugin
+" Language:	m17n database
+" Maintainer:	David Mandelberg <david@mandelberg.org>
+" Last Change:	2025 Feb 21
+
+if exists('b:did_ftplugin')
+  finish
+endif
+let b:did_ftplugin = 1
+
+setlocal comments=:;;;,:;;,:;
+setlocal commentstring=;\ %s
+setlocal iskeyword=!-~,@,^34,^(,^),^92
+setlocal lisp
+setlocal lispwords=
+
+let b:undo_ftplugin = "setlocal comments< commentstring< iskeyword< lisp< lispwords<"
diff --git a/runtime/indent/m17ndb.vim b/runtime/indent/m17ndb.vim
new file mode 100644
index 0000000000..d25aafe135
--- /dev/null
+++ b/runtime/indent/m17ndb.vim
@@ -0,0 +1,14 @@
+" Vim indent file
+" Language:	m17n database
+" Maintainer:	David Mandelberg <david@mandelberg.org>
+" Last Change:	2025 Feb 21
+
+if exists("b:did_indent")
+  finish
+endif
+let b:did_indent = 1
+
+setlocal autoindent
+setlocal nosmartindent
+
+let b:undo_indent = "setlocal autoindent< smartindent<"
diff --git a/runtime/syntax/m17ndb.vim b/runtime/syntax/m17ndb.vim
new file mode 100644
index 0000000000..8d63e6f918
--- /dev/null
+++ b/runtime/syntax/m17ndb.vim
@@ -0,0 +1,28 @@
+" Vim syntax file
+" Language:	m17n database
+" Maintainer:	David Mandelberg <david@mandelberg.org>
+" Last Change:	2025 Feb 21
+"
+" https://www.nongnu.org/m17n/manual-en/m17nDBFormat.html describes the
+" syntax, but some of its regexes don't match the code. read_element() in
+" https://git.savannah.nongnu.org/cgit/m17n/m17n-lib.git/tree/src/plist.c
+" seems to be a better place to understand the syntax.
+
+if exists("b:current_syntax")
+ finish
+endif
+let b:current_syntax = "m17ndb"
+
+syn match m17ndbSymbol /\([^\x00- ()"\\]\|\\\_.\)\+/
+syn match m17ndbComment ";.*$" contains=@Spell
+syn match m17ndbInteger "-\?[0-9]\+"
+syn match m17ndbInteger "[0#]x[0-9A-Fa-f]\+"
+syn match m17ndbCharacter "?\(\_[^\\]\|\\\_.\)"
+syn region m17ndbText start=/\Z"/ skip=/\\\\\|\\"/ end=/"/
+syn region m17ndbPlist matchgroup=m17ndbParen start="(" end=")" fold contains=ALL
+
+hi def link m17ndbCharacter Character
+hi def link m17ndbComment Comment
+hi def link m17ndbInteger Number
+hi def link m17ndbParen Delimiter
+hi def link m17ndbText String
diff --git a/src/testdir/test_filetype.vim b/src/testdir/test_filetype.vim
index 3196856c03..bbc2d1f000 100644
--- a/src/testdir/test_filetype.vim
+++ b/src/testdir/test_filetype.vim
@@ -449,6 +449,9 @@ def s:GetFilenameChecks(): dict<list<string>>
     luau: ['file.luau'],
     lynx: ['lynx.cfg'],
     lyrics: ['file.lrc'],
+    m17ndb: ['any/m17n/file.ali', 'any/m17n/file.cs', 'any/m17n/file.dir', 'any/m17n/file.flt', 'any/m17n/file.fst', 'any/m17n/file.lnm', 'any/m17n/file.mic', 'any/m17n/file.mim', 'any/m17n/file.tbl',
+             'any/.m17n.d/file.ali', 'any/.m17n.d/file.cs', 'any/.m17n.d/file.dir', 'any/.m17n.d/file.flt', 'any/.m17n.d/file.fst', 'any/.m17n.d/file.lnm', 'any/.m17n.d/file.mic', 'any/.m17n.d/file.mim', 'any/.m17n.d/file.tbl',
+             'any/m17n-db/file.ali', 'any/m17n-db/file.cs', 'any/m17n-db/file.dir', 'any/m17n-db/FLT/file.flt', 'any/m17n-db/file.fst', 'any/m17n-db/LANGDATA/file.lnm', 'any/m17n-db/file.mic', 'any/m17n-db/MIM/file.mim', 'any/m17n-db/file.tbl'],
     m3build: ['m3makefile', 'm3overrides'],
     m3quake: ['file.quake', 'cm3.cfg'],
     m4: ['file.at', '.m4_history'],
diff --git a/src/version.c b/src/version.c
index fe6ebd28db..bd7b1f68d8 100644
--- a/src/version.c
+++ b/src/version.c
@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1140,
 /**/
     1139,
 /**/