diff --git a/.github/actions/spell-check/expect.txt b/.github/actions/spell-check/expect.txt
index b11d260d49..244ac0200b 100644
--- a/.github/actions/spell-check/expect.txt
+++ b/.github/actions/spell-check/expect.txt
@@ -939,6 +939,7 @@ INVALIDARG
 invalidoperatioexception
 IObject
 iobjectwithsitesetsite
+IObservable
 IOle
 iolewindowcontextsensitivehelp
 iomanip