The arrangement of leaves on a stem and the principles that govern such arrangement, phyllotactic spirals form a distinctive class of patterns in nature.
In botany, phyllotaxis (from Ancient Greek φύλλον (phúllon) 'leaf' and τάξις (táxis) 'arrangement') or phyllotaxy is the arrangement of leaves on a plant stem. Phyllotactic spirals form a distinctive class of patterns in nature.

English
Noun
phyllotaxy (countable and uncountable, plural phyllotaxies)
- phyllotaxis