diff --git a/documentation/ref-manual/ref-variables.xml b/documentation/ref-manual/ref-variables.xml
index f1a62dcf40..c1dce009b6 100644
--- a/documentation/ref-manual/ref-variables.xml
+++ b/documentation/ref-manual/ref-variables.xml
@@ -9042,6 +9042,28 @@ recipes-graphics/xorg-font/font-alias_1.0.3.bb:PR = "${INC_PR}.3"
             </glossdef>
         </glossentry>
 
+        <glossentry id='var-TUNECONFLICT'><glossterm>TUNECONFLICT[&lt;feature&gt;]</glossterm>
+            <glossdef>
+                <para>
+                    Specifies CPU or Application Binary Interface (ABI)
+                    tuning features that conflict with &gt;feature&lt;.
+                </para>
+
+                <para>
+                    Known tuning conflicts are specified in the machine include
+                    files in the
+                    <ulink url='&YOCTO_DOCS_DEV_URL;#source-directory'>Source Directory</ulink>.
+                    Here is an example from the
+                    <filename>meta/conf/machine/include/mips/arch-mips.inc</filename>
+                    include file that lists the "o32" and "n64" features as
+                    conflicting with the "n32" feature:
+                    <literallayout class='monospaced'>
+     TUNECONFLICTS[n32] = "o32 n64"
+                    </literallayout>
+                </para>
+            </glossdef>
+        </glossentry>
+
         <glossentry id='var-TUNEVALID'><glossterm>TUNEVALID[&lt;feature&gt;]</glossterm>
             <glossdef>
                 <para>