pinnule

[ pin-yool ]

/ ˈpɪn yul /

Save This Word!

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.

QUIZ

THINGAMABOB OR THINGUMMY: CAN YOU DISTINGUISH BETWEEN THE US AND UK TERMS IN THIS QUIZ?

Do you know the difference between everyday US and UK terminology? Test yourself with this quiz on words that differ across the Atlantic.

Question 1 of 7

In the UK, COTTON CANDY is more commonly known as…

candystring

candyfloss

candypuff

TAKE THE QUIZ TO FIND OUT

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. 2023

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.