rachis

/ˈreɪkɪs/

Definitions of rachis

1. noun

   axis of a compound leaf or compound inflorescence
   type of:

   axis

   the main stem or central part about which plant organs or plant parts such as branches are arranged
2. noun

   the series of vertebrae forming the axis of the skeleton and protecting the spinal cord
   synonyms: back, backbone, spinal column, spine, vertebral column

   types:

   notochord

   a flexible rodlike structure that forms the supporting axis of the body in the lowest chordates and lowest vertebrates and in embryos of higher vertebrates

   chine

   backbone of an animal

   urochord

   a notochord of a larval tunicate typically confined to the caudal region

   type of:

   skeletal structure

   any structure created by the skeleton of an organism