diff --git a/stdlib/_operator.pyi b/stdlib/_operator.pyi
index 81a72b551..f6473e469 100644
--- a/stdlib/_operator.pyi
+++ b/stdlib/_operator.pyi
@@ -68,7 +68,7 @@ def getitem(__a: Sequence[_T], __b: SupportsIndex) -> _T: ...
 def getitem(__a: Sequence[_T], __b: slice) -> Sequence[_T]: ...
 @overload
 def getitem(__a: Mapping[_K, _V], __b: _K) -> _V: ...
-def indexOf(__a: Sequence[_T], __b: _T) -> int: ...
+def indexOf(__a: Iterable[_T], __b: _T) -> int: ...
 @overload
 def setitem(__a: MutableSequence[_T], __b: SupportsIndex, __c: _T) -> None: ...
 @overload