Close a %frame programatically

How do I close a top-level %frame?
Of course I can click on the close button the OS provides me at the top right corner.
But what if the program I am running wants to initiate the close without user involvement? And then go on running doing other things that do not involve the %frame?
I'm running all this in DrRacket on Devuan Linux.
-- hendrik

Is it enough to hide the window instead of closing it? You can use (send a-window show #f' to hide it.