cotton grass definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
any of a genus (Eriophorum) of grasslike plants of the sedge family, with flower heads resembling tufts of cotton, common in northern bogs
cotton grass definition by American Heritage Dictionary
Any of various perennial grasslike plants of the genus Eriophorum native chiefly to wet places in northern temperate and cold regions and bearing at maturity one or more conspicuous tufts of cottony bristles.