Pinnules

Part of speech: noun

Definitions

1. Small leaf-like formations occurring on fronds or the compound structures of certain plants are indicated by this term
2. It refers to the smaller segments or leaflets of more complex leaf arrangements found in various ferns
3. Features referring to the tiny leaflet segments attached to a larger compound leaf or fern frond

Etymology: "Pinnules" is the plural of "pinnule", which is the ultimate source of the small leaflets that make up a fern frond or the tiny branchlets of some seaweeds and feathers. The English word comes from Latin "pinnula", a diminutive of "pinna", meaning feather, wing, or fin. The Latin suffix "-ula" marks something as small, so the word literally means a little feather. The same Latin root "pinna" gave English "pinna", the outer ear, and "pinnacle", a little peak or turret, from a related diminutive. Each carries the image of something small and projecting from a larger whole.