The sentence "Immer, wenns nix worn is, nennt mas' Schwegel" is in south german dialect and means: Always when you failed to make a special stop as intended, you could name the result "Schwegel". I heard this statement from an old organ builder.
I had to look up the definition of Schwegel or Schwiegel by myself. I myself remember it as a flutelike stop of higher pitch (2'), but my search results are somehow ambivalent (like the statement states).
it is defined like Harfenprincipal - a narrow principal.
it is defined as comming from the old german word suegala which means shinbone and means Querflöte - as in former times flutes where made from bones.
To make it short - nobody exactly knows what this stop name stands for so you could take this name for every stop.
With best regards - Martin
You can play Bach on every organ.