pinnule
[pin-yool]
- 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
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for pinnule
Historical Examples
The index reference for "Pinnule" should probably be 59, rather than 66, but was not changed.
The Elements of BotanyAsa Gray
Pinnule, a secondary division of a bipinnate or tripinnate leaf, 66.
The Elements of BotanyAsa Gray
Sporangia in oblong sori under a reflexed tooth of a pinnule; indusium broad; rachis dark and shining.
The Fern Lover's CompanionGeorge Henry Tilton
The sori are placed on small veins which grow outwards from the midrib of the pinnule.
How to Know the FernsS. Leonard Bastin
They occur about midway between the central vein of the pinnule and the margin of the leaf.
How to Know the FernsS. Leonard Bastin
pinnule
pinnula (ˈpɪnjʊlə)
- 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
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Word Origin
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
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.
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The American Heritage® Science Dictionary
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