diff --git a/doc/lispref/nonascii.texi b/doc/lispref/nonascii.texi
index 8e9d62429c2..97bc85f152e 100644
--- a/doc/lispref/nonascii.texi
+++ b/doc/lispref/nonascii.texi
@@ -722,7 +722,10 @@ The value of this variable is a char-table that specifies, for each
 character, a symbol whose name is the script to which the character
 belongs, according to the Unicode Standard classification of the
 Unicode code space into script-specific blocks.  This char-table has a
-single extra slot whose value is the list of all script symbols.
+single extra slot whose value is the list of all script symbols.  Note
+that Emacs' classification of characters into scripts is not a 1-for-1
+reflection of the Unicode standard, e.g. there is no @samp{symbol}
+script in Unicode.
 @end defvar
 
 @defvar char-width-table