- Any of various plants of the genus Trillium, of North America, the Himalaya Mountains, and eastern Asia, usually having a cluster of three leaves and a variously colored, three-petaled flower. Also called birthroot, wake-robin. (noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.