Megarectum is a medical condition that refers to an abnormally dilated rectum. In some cases, it can cause difficulty in passing stools and may cause fecal incontinence. If you are looking for synonyms for the word megarectum, there are several terms you can use. These include rectal dilation, rectal distention, rectal enlargement, rectal expansion, and rectal hypertrophy. While these words may not be commonly used in everyday conversations, they are essential in the medical field. If you suspect that you may have rectal problems, it is advisable to seek medical attention immediately.