from
The Collaborative International Dictionary of English v.0.48
Pinnate \Pin"nate\, Pinnated \Pin"na*ted\, a. [L. pinnatus
feathered, fr. pinna a feather. See {Pin} a peg, {Pen}
feather.]
1. (Bot.) Consisting of several leaflets, or separate
portions, arranged on each side of a common petiole, as
the leaves of a rosebush, a hickory, or an ash. See
{Abruptly pinnate}, and Illust., under {Abruptly}.
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2. (Zool.) Having a winglike tuft of long feathers on each
side of the neck.
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{Pinnated grouse} (Zool.), the prairie chicken.
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