\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}.
2. (Zo["o]l.) Having a winglike tuft of long feathers on each
   side of the neck.
{Pinnated grouse} (Zo["o]l.), the prairie chicken.