pinnule

[ pin-yool ]

noun

1. Zoology.
   1. a part or organ resembling a barb of a feather, a fin, or the like.
   2. a finlet.
2. Botany. a secondary pinna, one of the pinnately disposed divisions of a bipinnate leaf.
3. a metal plate with a small hole in it, used as a sight in a quadrant.

pinnule

/ ˈpɪnjʊlə; ˈpɪnjuːl /

noun

1. any of the lobes of a leaflet of a pinnate compound leaf, which is itself pinnately divided
2. zoology any feather-like part, such as any of the arms of a sea lily

pinnule

/ pĭn′yo̅o̅l /

1. 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.

Derived Forms

• ˈpinnular, adjective

Other Words From

• pin·nu·lar [pin, -y, uh, -ler], adjective

Word History and Origins

Origin of pinnule¹

1585–95; < Latin pinnula pinnula

Word History and Origins

Origin of pinnule¹

C16: from Latin pinnula, diminutive of pinna feather

Example Sentences

The cordate pinnules sometimes found here are commoner in Europe.

From Project Gutenberg

Its value was much impaired by his preference of the antique “pinnules” to telescopic sights on quadrants.

From Project Gutenberg

Arms fork once to thrice, and bear pinnules on each or on every other brachial.

From Project Gutenberg

It is probably a fern, more minute in its pinnules than even our smallest specimens of true maidenhair.

From Project Gutenberg

Ordinary frond and forked and crested varieties of the same, the crest arising from the inordinate development of the margins of the pinnules.

From Project Gutenberg