Bowel Movement

defecation, expulsion of feces; feces, bodily waste, excrement

Defecation is the act or process by which organisms eliminate solid or semisolid waste material (feces) from the digestive tract via the anus. Humans expel feces anywhere from a few times daily to a few times weekly; sloths can go a week without expelling. Waves of muscular contraction known as peristalsis in the walls of the colon move fecal matter through the digestive tract towards the rectum. Undigested food may also be expelled this way; this process is called egestion.
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Bowel movement n. Abbr. BM 1. The discharge of waste matter from the large intestine; defecation. 2. [more]Bowel movement - Community and Resources

Noun
1. a euphemism for defecation; "he had a bowel movement"
(synonym) movement, bm
(hypernym) defecation, laxation, shitting

Synonyms and related words:
BM, bloody flux, buffalo chips, ca-ca, catharsis, coprolite, coprolith, cow chips, cow flops, cow pats, crap, defecation, dejection, diarrhea, dingleberry, droppings, dung, dysentery, evacuation, feces, feculence, flux, guano, jakes, lientery, loose bowels, manure, movement, night soil, ordure, purgation, purge, runs, sewage, sewerage, shit, shits, stool, trots, turd, turistas, voidance