colorectal leiomyoma (Monarch Disease Ontology id MONDO_0003299) is a well-circumscribed benign smooth muscle neoplasm arising from the colorectal area. It is characterized by the presence of spindle cells with cigar-shaped nuclei, interlacing fascicles, and a whorled pattern. Also known as: colorectum leiomyoma, large bowel leiomyoma, large intestine leiomyoma, leiomyoma of large bowel, leiomyoma of large intestine, leiomyoma of the large bowel, leiomyoma of the large intestine.