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fo·li·um  (fōle-əm)
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Tweet n.pl. fo·li·a(-le-ə) 1. Geology A thin, leaflike layer or stratum occurring especially in metamorphic rock. 2. Mathematics A plane cubic curve having a single loop, a node, and two ends asymptotic to the same line. [Latin, leaf; see bhel-3 in the Appendix of Indo-European roots.]  (click for a larger image) foliumThe equation of the folium of Descartes is x3 + y3 = 3axy. |
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
