1 definition by Portnoy
Somnambowelism is a portmanteau or "frankenword" combination of the words "somnambulism" and "bowel," and it describes the activity of "sleep pooping," or getting up to take a dump in the middle of the night, without partial or total recall of the event the following day. Somnambowelism is not considered to be any more dangerous than normal somnambulism, but it is regarded as markedly more disgusting, potentially vile, and possibly catastrophic to the general cleanliness of your overpriced bed.
Upon realizing he was afflicted with the rare and unfortunate sleep walking disorder sub-classified as somnambowelism, Portnoy, immediately trekked out to Linens and Things and purchased dark brown bedsheets.
by Portnoy October 3, 2005