pinnule

[ pin-yool ]

/ ˈpɪn yul /

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noun

Zoology.

a part or organ resembling a barb of a feather, a fin, or the like.
a finlet.

Botany. a secondary pinna, one of the pinnately disposed divisions of a bipinnate leaf.

a metal plate with a small hole in it, used as a sight in a quadrant.

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Origin of pinnule

1585–95; <Latin pinnulapinnula

OTHER WORDS FROM pinnule

pin·nu·lar

[pin-yuh-ler], /ˈpɪn yə lər/, adjective

Words nearby pinnule

pinner, pinnigrade, pinniped, pinnula, pinnulate, pinnule, pinny, pin oak, Pinocchio, Pinocchio, The Adventures of, Pinochet

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use pinnule in a sentence

Each pinnule has its edges so much recurved that the whole forms a sort of pouch, apparently filled with sporangia.
Beautiful Ferns|Daniel Cady Eaton
They occur about midway between the central vein of the pinnule and the margin of the leaf.
How to Know the Ferns|S. Leonard Bastin
The sori are in the form of lines which branch out from the lower part of the pinnule in a fan-shaped manner.
How to Know the Ferns|S. Leonard Bastin
The sori are placed on small veins which grow outwards from the midrib of the pinnule.
How to Know the Ferns|S. Leonard Bastin

Sporangia in oblong sori under a reflexed tooth of a pinnule; indusium broad; rachis dark and shining.
The Fern Lover's Companion|George Henry Tilton

British Dictionary definitions for pinnule

pinnule

pinnula (ˈpɪnjʊlə)

/ (ˈpɪnjuːl) /

noun plural pinnules or pinnulae (ˈpɪnjʊˌliː)

any of the lobes of a leaflet of a pinnate compound leaf, which is itself pinnately divided

zoology any feather-like part, such as any of the arms of a sea lily

Derived forms of pinnule

pinnular, adjective

Word Origin for pinnule

C16: from Latin pinnula, diminutive of pinna feather

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for pinnule

pinnule

[ pĭn′yōōl ]

Any of the smaller leaflets into which each leaflet of a bipinnately compound leaf is subdivided. The leaves of many ferns are divided into pinnules.