diff --git a/gaboshlib/g_read_csv.sh b/gaboshlib/g_read_csv.sh
index 6876f00..eefbb5d 100644
--- a/gaboshlib/g_read_csv.sh
+++ b/gaboshlib/g_read_csv.sh
@@ -45,7 +45,7 @@ function g_read_csv {
   # prepare varnames from headline(s)
   for g_headline_item in "${g_csv_headline_array_ref[@]}"
   do
-    g_csv_headline_array+=("${g_headline_item//[^a-zA-Z0-9]/}")
+    g_csv_headline_array+=("${g_headline_item//[^a-zA-Z0-9_]/}")
   done
 
   # read last lines if defined or complete csv file