n.
A hollow cell in the excretory system of certain invertebrates, including flatworms and rotifers, containing a tuft of rapidly beating cilia that serve to propel waste products into excretory tubules.
The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.
