diff --git a/.cspell/custom-dictionary.txt b/.cspell/custom-dictionary.txt
index 5123e47d..975becbe 100644
--- a/.cspell/custom-dictionary.txt
+++ b/.cspell/custom-dictionary.txt
@@ -63,6 +63,7 @@ cryo
 cstart
 cstep
 csvfile
+cumsum
 custom-dictionary
 cval
 cvdist