rachis
nounUK /ˈreɪkɪs/
US /ˈreɪkɪs/
The main stem in the middle of a feather or a leaf.
The little bird's feathers have a strong rachis down the center.
OTHER MEANINGS
2. The central stalk of a compound leaf, to which the leaflets are attached.
Each leaflet grows along the rachis of the fern frond.
3. The part of a feather's shaft that bears the barbs.
The barbs branch off both sides of the rachis.
4. The spinal column or a similar central axis in anatomy.
The surgeon examined the rachis for any signs of injury.
5. The central stem of an inflorescence, such as a spike of flowers.
Small flowers clustered tightly along the rachis of the wheat plant.