Main Entry: in·tes·ti·nal Pronunciation: in-'tes-t&n-&l, -'tes(t)-n&l, -'tes-&n-&l, Britoften"in-(")tes-'tIn-&l Function: adjective 1 a: affecting or occurring in the intestine 0<intestinal digestion><intestinal catarrh> b: living in the intestine intestinal flora> intestinal worm> 2: of, relating to, or beingthe intestine intestinal canal> —in·tes·ti·nal·ly/-E/adverb