Any of various plants of the genus Trillium, of North America, the Himalaya Mountains, and eastern Asia, having a whorl of three leaflike bracts and a usually white, reddish, or yellow three-petaled flower. Also called birthroot, wake-robin.
[New Latin Trillium, genus name, probably from Swedish trilling, triplet (from its three leaflike bracts), from obsolete Swedish tri, three, from Old Swedish thrīr; see trei- in the Appendix of Indo-European roots.]
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Indo-European & Semitic Roots Appendices
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