Definition of pinnate in English:

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Pronunciation: /ˈpināt/
Pronunciation: /ˈpinət/


1(Of a compound leaf) having leaflets arranged on either side of the stem, typically in pairs opposite each other.
Example sentences
  • Immatures have a weakly developed taproot, and have pinnate compound leaves with two or three leaflets.
  • In 1794, Moench named A. tuberosa and described it as having tuberous roots, unevenly pinnate leaflets, and purple flowers in lateral racemes.
  • Green stems are interconnected by sensitive petioles and bear pinnate leaves.
1.1 Zoology (Especially of an invertebrate animal) having branches, tentacles, etc., on each side of an axis, like the vanes of a feather.
Example sentences
  • The microsporophyll of Lepidopteris has been reconstructed as a pinnate axis with short branches bearing clusters of small elongate pollen sacs fused at the base.
  • Arrangement of septa in earliest stages pinnate in all quadrants.
  • The colonies are erect, typically delicate; reticulate (net-like) or pinnate (fern-like).



Example sentences
  • There it was, that, year after year, and each successive season, I studied the habits of the Pinnated Grouse.
  • Pinnated Bittern (Botaurus pinnatus) is a species that is visually similar to the American Bittern (B. lentiginosus) which is more familiar to North American observers.


Example sentences
  • The plant has 45 cm high clustered leafy stems with pinnately arranged pale green lance-shaped leaflets obliquely banded with pure white.
  • Each sporangial complex is born on a branch system that dichotomizes twice, with each resulting branch tip branching pinnately and ending in a sporangium.
  • Trichopitys lacks the short-shoot, long-shoot morphology and its ovules are born in pinnately branched systems that develop in the axils of leaves.


Pronunciation: /piˈnāSHən/
Example sentences
  • Trabs rise steeply or sub-vertically from surface of pinnation, which is approximately 1/3-1/4 of wall thickness from gastral margin.
  • Anthaspidellid skeleton with surface of pinnation approximately at midwall, from which trabs rise upward and outward, or inward, to meet dermal and gastral surfaces at acute angles.
  • The angle of pinnation was found by placing a protractor along the central tendon and measuring the angle of an individual fiber to the nearest 0.5 deg.


Early 18th century: from Latin pinnatus 'feathered', from pinna, penna (see pinna).

For editors and proofreaders

Syllabification: pin·nate

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