cytochalasin

[sī′tō-kălə-sĭn, -zĭn, -kə-lā-]
n.
  1. Any of a group of substances derived from molds that interfere with the division of cytoplasm, inhibit cell movement, and cause extrusion of the nucleus.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.