diff --git a/doc/src/sgml/acronyms.sgml b/doc/src/sgml/acronyms.sgml
index 4e5ec983c0..13bd819eb1 100644
--- a/doc/src/sgml/acronyms.sgml
+++ b/doc/src/sgml/acronyms.sgml
@@ -684,6 +684,16 @@
     </listitem>
    </varlistentry>
 
+   <varlistentry>
+    <term><acronym>TLS</acronym></term>
+    <listitem>
+     <para>
+      <ulink url="https://en.wikipedia.org/wiki/Transport_Layer_Security">
+      Transport Layer Security</ulink>
+     </para>
+    </listitem>
+   </varlistentry>
+
    <varlistentry>
     <term><acronym>TOAST</acronym></term>
     <listitem>