Word Study
rectum
OXFORD DICTIONARY
rectum, n. (pl. rectums or recta) the final section of the large intestine, terminating at the anus.
Etymology
L rectum (intestinum) straight (intestine)
THESAURUS
rectum
abdomen, anus, appendix, blind gut, bowels, brain, cecum, colon, duodenum, endocardium, entrails, foregut, giblets, gizzard, guts, heart, hindgut, innards, inner mechanism, insides, internals, intestine, inwards, jejunum, kidney, kishkes, large intestine, liver, liver and lights, lung, midgut, perineum, pump, pylorus, small intestine, spleen, stomach, ticker, tripes, vermiform appendix, viscera, vitals, worksFor further exploring for "rectum" in Webster Dictionary Online