diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst
index 7af7a7c0d7c47b..7eb1563e9a3582 100644
--- a/Doc/library/sys.rst
+++ b/Doc/library/sys.rst
@@ -883,7 +883,7 @@ always available. Unless explicitly noted otherwise, all variables are read-only
 
 .. function:: getswitchinterval()
 
-   Return the interpreter's "thread switch interval"; see
+   Return the interpreter's "thread switch interval" in seconds; see
    :func:`setswitchinterval`.
 
    .. versionadded:: 3.2