Definition of pinnate in English:



  • 1(of a compound leaf) having leaflets arranged on either side of the stem, typically in pairs opposite each other.

    • ‘All of these foliage forms are planate pinnate fronds, frequently with open venation.’
    • ‘It has pinnate leaves and racemes of lilac pink flowers, which are slightly fragrant.’
    • ‘Green stems are interconnected by sensitive petioles and bear pinnate leaves.’
    • ‘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.’
    1. 1.1Zoology (especially of an invertebrate animal) having branches, tentacles, etc., on each side of an axis, like the vanes of a feather.
      • ‘The colonies are erect, typically delicate; reticulate (net-like) or pinnate (fern-like).’
      • ‘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.’


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