diff --git a/src/include/ngspice/cpdefs.h b/src/include/ngspice/cpdefs.h
index 8fc78dfd8..7dbfa713f 100644
--- a/src/include/ngspice/cpdefs.h
+++ b/src/include/ngspice/cpdefs.h
@@ -47,6 +47,9 @@ struct comm {
     char *co_help;
 };
 
+/* These macros are used only in definitions of commands, where they
+ * are used as the upper limit to the number of arguments for a command
+ * when that number is essentially arbitrary, with NLOTS being even more */
 #define LOTS        1000
 #define NLOTS       10000