diff --git a/gunicorn/config.py b/gunicorn/config.py
index ae387d31..4c357aaf 100644
--- a/gunicorn/config.py
+++ b/gunicorn/config.py
@@ -820,14 +820,16 @@ class PreloadApp(Setting):
 class Sendfile(Setting):
     name = "sendfile"
     section = "Server Mechanics"
-    cli = ["--sendfile"]
+    cli = ["--no-sendfile"]
     validator = validate_bool
-    action = "store_true"
+    action = "store_false"
     default = True
     desc = """\
-        Enables or disables the use of ``sendfile()``.
+        Disables the use of ``sendfile()``.
 
         .. versionadded:: 19.2
+        .. versionchanged:: 19.4
+            Swapped --sendfile with --no-sendfile to actually allow disabling
         """
 
 class Chdir(Setting):