diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index c76ec52c55..fd390b03ac 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -19905,7 +19905,7 @@ SELECT NULLIF(value, '(none)') ...
        </para>
        <para>
         Extracts the lower bound of the range (<literal>NULL</literal> if the
-        range is empty or the lower bound is infinite).
+        range is empty or unspecified).
        </para>
        <para>
         <literal>lower(numrange(1.1,2.2))</literal>
@@ -19923,7 +19923,7 @@ SELECT NULLIF(value, '(none)') ...
        </para>
        <para>
         Extracts the upper bound of the range (<literal>NULL</literal> if the
-        range is empty or the upper bound is infinite).
+        range is empty or unspecified).
        </para>
        <para>
         <literal>upper(numrange(1.1,2.2))</literal>
@@ -19991,7 +19991,8 @@ SELECT NULLIF(value, '(none)') ...
         <returnvalue>boolean</returnvalue>
        </para>
        <para>
-        Is the range's lower bound infinite?
+        Is the range's lower bound unspecified?  A +/-Infinity lower
+        bound returns false.
        </para>
        <para>
         <literal>lower_inf('(,)'::daterange)</literal>
@@ -20008,7 +20009,8 @@ SELECT NULLIF(value, '(none)') ...
         <returnvalue>boolean</returnvalue>
        </para>
        <para>
-        Is the range's upper bound infinite?
+        Is the range's upper bound unspecified?  A +/-Infinity upper
+        bound returns false.
        </para>
        <para>
         <literal>upper_inf('(,)'::daterange)</literal>
@@ -20063,7 +20065,7 @@ SELECT NULLIF(value, '(none)') ...
        </para>
        <para>
         Extracts the lower bound of the multirange (<literal>NULL</literal> if the
-        multirange is empty or the lower bound is infinite).
+        multirange is empty or unspecified).
        </para>
        <para>
         <literal>lower('{[1.1,2.2)}'::nummultirange)</literal>
@@ -20081,7 +20083,7 @@ SELECT NULLIF(value, '(none)') ...
        </para>
        <para>
         Extracts the upper bound of the multirange (<literal>NULL</literal> if the
-        multirange is empty or the upper bound is infinite).
+        multirange is empty or unspecified).
        </para>
        <para>
         <literal>upper('{[1.1,2.2)}'::nummultirange)</literal>
@@ -20149,7 +20151,8 @@ SELECT NULLIF(value, '(none)') ...
         <returnvalue>boolean</returnvalue>
        </para>
        <para>
-        Is the multirange's lower bound infinite?
+        Is the multirange's lower bound unspecified?  A +/-Infinity lower
+        bound returns false.
        </para>
        <para>
         <literal>lower_inf('{(,)}'::datemultirange)</literal>
@@ -20166,7 +20169,8 @@ SELECT NULLIF(value, '(none)') ...
         <returnvalue>boolean</returnvalue>
        </para>
        <para>
-        Is the multirange's upper bound infinite?
+        Is the multirange's upper bound unspecified?  A +/-Infinity upper
+        bound returns false.
        </para>
        <para>
         <literal>upper_inf('{(,)}'::datemultirange)</literal>