diff --git a/runtime/syntax/ahdl.vim b/runtime/syntax/ahdl.vim
index 664bd38..3a40dcf 100644
--- a/runtime/syntax/ahdl.vim
+++ b/runtime/syntax/ahdl.vim
@@ -38,7 +38,7 @@
 
 syn keyword ahdlTodo contained TODO
 
-" String contstants
+" String constants
 syn region ahdlString start=+"+  skip=+\\"+  end=+"+
 
 " valid integer number formats (decimal, binary, octal, hex)