trillium
Concise Oxford English Dictionary © 2008 Oxford University Press:
trillium /ˈtrɪlɪəm/
▶noun (pl. trilliums) a plant with a solitary three-petalled flower above a whorl of three leaves. [Genus Trillium.]
– origin mod. L., appar. an alt. of Swed. trilling ‘triplet’.
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