Folium ( la, folium, "leaf") may refer to * a leaf of a book: see

recto and verso ''Recto'' is the "right" or "front" side and ''verso'' is the "left" or "back" side when text is written or printed on a leaf of paper () in a bound item such as a codex, book, broadsheet, or pamphlet. Etymology The terms are shortened from ...

Folium of Descartes In geometry, the folium of Descartes (; named for René Decartes) is an algebraic curve defined by the implicit equation :x^3 + y^3 - 3 a x y = 0. History The curve was first proposed and studied by René Descartes in 1638. Its claim to fame ...

, an algebraic curve *

Folium (spider) This glossary describes the terms used in formal descriptions of spiders; where applicable these terms are used in describing other arachnids. Links within the glossary are shown . Terms A Abdomen or opisthosoma: One of the two main body parts ...

, a marking on the abdomen of a spider

Brain anatomy

Folium (brain) The cerebellum (Latin for "little brain") is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as or even larger. In humans, the cerebe ...

Folium vermis The folium vermis is a short, narrow, concealed band at the posterior extremity of the vermis, consisting apparently of a single folium, but in reality marked on its upper and under surfaces by secondary fissures. Laterally, it expands in either ...

Botany

Turnsole Turnsole or folium was a dyestuff prepared from the annual plant ''Chrozophora tinctoria''. History Turnsole became a mainstay of medieval manuscript illuminators starting with the development of the technique for extracting it in the thirteenth ...

or folium, a dyestuff * Folium Phyllostachydis, processed leaves of bamboo *

Hydrangeae Dulcis Folium ''Hydrangea macrophylla'' is a species of flowering plant in the family (biology), family Hydrangeaceae, native plant, native to Japan. It is a deciduous shrub growing to tall by broad with large heads of pink or blue flowers in summer and aut ...

, processed leaves of hydrangea {{disambig