myofibroma

[mī′ō-fī-brōmə]
n.
  1. A benign tumor that consists chiefly of fibrous connective tissue, with variable numbers of muscle cells forming portions of the tumor.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.