Robert Peters wrote:

>Being a native German
>I instantly understood the phrase "mein Unterleib" to be a euphemism.
>Beethoven wouldn't have been too shy to write things like "mein Magen" if
>he really meant his abdomen.

Not so much a euphemism as it is an example of synecdoche (a whole standing
for a part).  "Unterleib" might refer to "anything down there," from the
bladder to the uterus (in a woman) to . . .  well, you get the point.
I think it's fair to say though that without more context the remark by
itself offers no evidence Beethoven was referring to any specific organ.

John Dalmas
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