folium

American  

[foh-lee-uhm] / ˈfoʊ li əm /

noun

plural

folia

1. a thin leaflike stratum or layer; a lamella.

2. Geometry. a loop; part of a curve terminated at both ends by the same node. Equation: x 3 + y 3 = 3 axy.

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folium British  

/ ˈfəʊlɪəm /

noun

1. a plane geometrical curve consisting of a loop whose two ends, intersecting at a node, are asymptotic to the same line. Standard equation: x ³ + y ³=3a xy where x = y +a is the equation of the line

2. any thin leaflike layer, esp of some metamorphic rocks

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folium Scientific  

/ fō′lē-əm /

plural

folia

1. A thin, leaflike layer or stratum occurring especially in metamorphic rock.

2. A plane cubic curve having a single loop, a node, and two ends asymptotic to the same line.

3. Also called folium of Descartes

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Etymology

Origin of folium

1840–50; < New Latin, Latin: literally, a leaf

Example Sentences

Graph the tangent line along with the folium.

From Textbooks • Mar. 30, 2016

Many plane curves in mathematics are named after the people who first investigated them, like the folium of Descartes or the spiral of Archimedes.

From Textbooks • Mar. 30, 2016

Bis denum Rutæ folium, salis et breve granum, Juglandesque duas, totidem cum corpore ficus; Hæc oriente die, parco conspersa Lycæo, Sumebat, metuens dederat quæ pocula mater.

From Curiosities of Medical Experience by Millingen, J. G. (John Gideon)

It is more remarkable for the singularity of its foliage than the beauty of its blossoms; the former exhibit a very good example of the folium pedatum of Linnæus, whence its name.

From The Botanical Magazine, Vol. 3 Or, Flower-Garden Displayed by Curtis, William

One suggestion, based on a supposed similar use of Fr. fleuret, literally a “little flower,” for the weapon, is that foil means a leaf, and must be referred in origin to Lat. folium.

From Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 5 "Fleury, Claude" to "Foraker" by Various