diff --git a/check_source/check_spelling_c_config.py b/check_source/check_spelling_c_config.py
index f4a361427be47916ff6bb539dc0fbabbe775011c..4c72181268b63d9c32ba58a04f09942e0fe95164 100644
--- a/check_source/check_spelling_c_config.py
+++ b/check_source/check_spelling_c_config.py
@@ -32,6 +32,7 @@ dict_custom = {
     "instantiation",
     "iterable",
     "merchantability",
+    "parallelization",
     "parallelized",
     "precalculate",
     "prepend",