That threatening feeling you get in the wake of a bowel movement. Typically an urgent feeling which results in immediate vacation of a place, task or conversation that you are in. Threatening bowel movements may strike at inappropriate times. You may experience the intense feeling without prior knowledge that you were anticipating a bowel movement.
Susie: How is your steak, Sharon?
Sharon: uh.. *abruptly leaves*

5 mins later

Susie: Are you okay?
Sharon: Yeah just had a major threatening bowel movement (TBM). But it has been expelled.
by JKF125 June 23, 2010
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