diff --git a/runtime/syntax/vim.vim b/runtime/syntax/vim.vim
index e5623528ea..b2a703eba9 100644
--- a/runtime/syntax/vim.vim
+++ b/runtime/syntax/vim.vim
@@ -274,7 +274,7 @@ syn match	vimDef	"\<def\>"		skipwhite nextgroup=vimCmdSep,vimComment,vimFuncPatt
 
 syn match	vimFunction	"\<fu\%[nction]\>!\=\s*\%(<[sS][iI][dD]>\|[sg]:\)\=\%(\i\|[#.]\|{.\{-1,}}\)\+"	contains=@vimFuncList skipwhite nextgroup=vimFuncParams
 syn match	vimDef	"\<def\s\+new\%(\i\|{.\{-1,}}\)\+"				contains=@vimDefList            nextgroup=vimDefParams
-syn match	vimDef	"\<def\>!\=\s*\%(<[sS][iI][dD]>\|[sg]:\)\=\%(\i\|[#.]\|{.\{-1,}}\)\+"		contains=@vimDefList            nextgroup=vimDefParams
+syn match	vimDef	"\<def\>!\=\s*\%(<[sS][iI][dD]>\|[sg]:\)\=\%(\i\|[#.]\|{.\{-1,}}\)\+"		contains=@vimDefList,vimMethodName            nextgroup=vimDefParams
 
 syn match	vimFuncComment	contained	+".*+ skipwhite skipempty nextgroup=vimFuncBody,vimEndfunction
 syn match	vimDefComment	contained	"#.*" skipwhite skipempty nextgroup=vimDefBody,vimEnddef
@@ -284,6 +284,7 @@ syn match	vimFuncSID	contained	"\c<sid>"
 syn match	vimFuncSID	contained	"\<[sg]:"
 syn keyword	vimFuncKey	contained	fu[nction]
 syn keyword	vimDefKey	contained	def
+syn keyword	vimMethodName	contained	empty len string
 
 syn region	vimFuncParams	contained	matchgroup=Delimiter start="(" skip=+\n\s*\\\|\n\s*"\\ + end=")" skipwhite skipempty nextgroup=vimFuncBody,vimFuncComment,vimEndfunction,vimFuncMod,vim9CommentError	contains=vimFuncParam,@vimContinue
 syn region	vimDefParams	contained	matchgroup=Delimiter start="("		   end=")" skipwhite skipempty nextgroup=vimDefBody,vimDefComment,vimEnddef,vimReturnType,vimCommentError	contains=vimDefParam,vim9Comment,vimFuncParamEquals
@@ -668,7 +669,7 @@ syn case match
 " (following Gautam Iyer's suggestion)
 " ==========================
 syn match	vimFunc              	"\%(\%([sSgGbBwWtTlL]:\|<[sS][iI][dD]>\)\=\%(\w\+\.\)*\I[a-zA-Z0-9_.]*\)\ze\s*("                	contains=vimFuncEcho,vimFuncName,vimUserFunc,vimExecute
-syn match	vimUserFunc	contained        	"\%(\%([sSgGbBwWtTlL]:\|<[sS][iI][dD]>\)\=\%(\w\+\.\)*\I[a-zA-Z0-9_.]*\)\|\<\u[a-zA-Z0-9.]*\>\|\<if\>"	contains=vimNotation
+syn match	vimUserFunc	contained        	"\%(\%([sSgGbBwWtTlL]:\|<[sS][iI][dD]>\)\=\%(\w\+\.\)*\I[a-zA-Z0-9_.]*\)\|\<\u[a-zA-Z0-9.]*\>\|\<if\>"	contains=vimNotation,vimMethodName
 syn keyword	vimFuncEcho	contained      	ec ech echo
 
 syn match	vimMap	"\<map\%(\s\+(\)\@="	skipwhite nextgroup=vimMapBang,vimMapMod,vimMapLhs
@@ -680,7 +681,9 @@ syn match vimUsrCmd	'^\s*\zs\u\%(\w*\)\@>\%([(#[]\|\s\+\%([-+*/%]\=\|\.\.\)=\)\@
 " ====================
 if !exists("g:vimsyn_noerror") && !exists("g:vimsyn_novimfunctionerror")
  " TODO: The new-prefix exception should only apply to constructor definitions.
- syn match	vimFunctionError	"\s\zs\%(new\)\@![a-z0-9]\i\{-}\ze\s*("			contained contains=vimFuncKey,vimFuncBlank
+ " TODO: The |builtin-object-methods| exception should only apply to method
+ " definitions.
+ syn match	vimFunctionError	"\s\zs\%(empty\|len\|new\|string\)\@![a-z0-9]\i\{-}\ze\s*("		contained contains=vimFuncKey,vimFuncBlank
  syn match	vimFunctionError	"\s\zs\%(<[sS][iI][dD]>\|[sSgGbBwWtTlL]:\)\d\i\{-}\ze\s*("	contained contains=vimFuncKey,vimFuncBlank
  syn match	vimElseIfErr	"\<else\s\+if\>"
  syn match	vimBufnrWarn	/\<bufnr\s*(\s*["']\.['"]\s*)/
@@ -1256,6 +1259,7 @@ if !exists("skip_vim_syntax_inits")
  hi def link vimMenuPriority	Number
  hi def link vimMenuStatus	Special
  hi def link vimMenutranslateComment	vimComment
+ hi def link vimMethodName	vimFuncName
  hi def link vimMtchComment	vimComment
  hi def link vimNorm	vimCommand
  hi def link vimNotation	Special