diff --git a/doc/configuration.txt b/doc/configuration.txt
index 3ae6624..570abab 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -13220,7 +13220,7 @@
         INI     -> initializing
         SOCKERR -> socket error
         L4OK    -> check passed on layer 4, no upper layers testing enabled
-        L4TMOUT -> layer 1-4 timeout
+        L4TOUT  -> layer 1-4 timeout
         L4CON   -> layer 1-4 connection problem, for example
                    "Connection refused" (tcp rst) or "No route to host" (icmp)
         L6OK    -> check passed on layer 6