noun Tri·go·nia \trīˈgōnēə\

Definition of Trigonia

  1. 1 :  a genus of pearly-shelled bivalve mollusks (suborder Arcacea) including many extinct forms which characterize the Mesozoic rocks and a few living forms which survive on the coast of Australia

  2. 2 [New Latin; from the often triangular shape of the fruit] :  a genus (the type of the family Trigoniaceae) of chiefly climbing tropical American shrubs

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Origin and Etymology of trigonia

New Latin, from Latin trigonus triangular (from Greek trigōnos) + New Latin -ia; from the shells suggesting the form of a triangle — more at trigon

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to cast off or become cast off

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