the only species (Hippuris vulgaris
) of an aquatic
family (Hippuridaceae, order Callitrichales) of plants with tiny
flowers and narrow, hairlike leaves growing in thick
whorls around the slender
, erect stems
Webster’s New World College Dictionary, 4th Edition. Copyright © 2010 by
Houghton Mifflin Harcourt. All rights reserved.