diff --git a/check_source/check_spelling_c_config.py b/check_source/check_spelling_c_config.py
index ba2586ab6a37503d587c15a267ec675721c7d0a2..844dc9e39257c623cc37932944318a00d2969476 100644
--- a/check_source/check_spelling_c_config.py
+++ b/check_source/check_spelling_c_config.py
@@ -23,6 +23,7 @@
 # correct spelling but ignore
 dict_custom = {
     "adjoint", "adjugate",
+    "atomicity",
     "boolean",
     "decrement",
     "decrementing",
@@ -116,6 +117,7 @@ dict_custom = {
     "ack",
     "amiga",
     "bzflag",
+    "freebsd",
     "irix",
     "kde",
     "mozilla",