diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index bd12225cbe4..c7acc0f182f 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -4618,10 +4618,12 @@ restore_command = 'copy "C:\\server\\archivedir\\%f" "%p"'  # Windows
       </term>
       <listitem>
        <para>
-        Invalidate replication slots that have remained idle longer than this
-        duration. If this value is specified without units, it is taken as
-        seconds. A value of zero (the default) disables the idle timeout
-        invalidation mechanism. This parameter can only be set in the
+        Invalidate replication slots that have remained inactive (not used by
+        a <link linkend="protocol-replication">replication connection</link>)
+        for longer than this duration.
+        If this value is specified without units, it is taken as seconds.
+        A value of zero (the default) disables the idle timeout
+        invalidation mechanism.  This parameter can only be set in the
         <filename>postgresql.conf</filename> file or on the server command
         line.
        </para>
diff --git a/doc/src/sgml/system-views.sgml b/doc/src/sgml/system-views.sgml
index d3ff8c35738..4187191ea74 100644
--- a/doc/src/sgml/system-views.sgml
+++ b/doc/src/sgml/system-views.sgml
@@ -3003,7 +3003,7 @@ SELECT * FROM pg_locks pl LEFT JOIN pg_prepared_xacts ppx
         <listitem>
          <para>
           <literal>idle_timeout</literal> means that the slot has remained
-          idle longer than the configured
+          inactive longer than the configured
           <xref linkend="guc-idle-replication-slot-timeout"/> duration.
          </para>
         </listitem>
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
index c1c0f6c660d..281092279ac 100644
--- a/src/backend/replication/slot.c
+++ b/src/backend/replication/slot.c
@@ -1892,7 +1892,7 @@ InvalidatePossiblyObsoleteSlot(uint32 possible_causes,
 		 * max_slot_wal_keep_size is set to -1 and
 		 * idle_replication_slot_timeout is set to 0 during the binary
 		 * upgrade. See check_old_cluster_for_valid_slots() where we ensure
-		 * that no invalidated before the upgrade.
+		 * that no slot was invalidated before the upgrade.
 		 */
 		Assert(!(*invalidated && SlotIsLogical(s) && IsBinaryUpgrade));