When the rectum protrudes from the anal cavity. This can either be a result of sodomy or over exerting one's self while defacating.
Did you see that red blob come out of that chicks ass while she was shitting on his face?!?!? She's got an anal prolapse.
One who has an abnormal obsession, or sexual attraction to mycobacterium. Usually this person is a microbiologist or biochemistry major in college.
Don't let Phil touch the mycobacteria again, he is a mycophiliac.