diff --git a/reference/strings/functions/addslashes.xml b/reference/strings/functions/addslashes.xml
index 4758845837..3cf7af4fc1 100644
--- a/reference/strings/functions/addslashes.xml
+++ b/reference/strings/functions/addslashes.xml
@@ -17,7 +17,7 @@
    to be quoted in database queries etc.  These characters are
    single quote (<literal>'</literal>), double quote
    (<literal>"</literal>), backslash (<literal>\</literal>)
-   and NULL (the &null; byte).
+   and NUL (the &null; byte).
   </para>
   <para>
    An example use of <function>addslashes</function> is when you're