noun, plural ra·chis·es, rach·i·des [rak-i-deez, rey-ki-] /ˈræk ɪˌdiz, ˈreɪ kɪ-/.
- the axis of an inflorescence when somewhat elongated, as in a raceme.
- (in a pinnately compound leaf or frond) the prolongation of the petiole along which the leaflets are disposed.
- any of various axial structures.
Origin of rachis
Related formsra·chid·i·an [ruh-kid-ee-uh n] /rəˈkɪd i ən/, ra·chi·al [rey-kee-uh l] /ˈreɪ ki əl/, ra·chid·i·al, adjective
Examples from the Web for rachis
The outline of the leafy part is triangular in form, and on either side of the rachis are the tapering pinnæ.How to Know the Ferns|S. Leonard Bastin
Meanwhile the Pope has persuaded the Lombard king Rachis to go into a monastery.The Roman and the Teuton|Charles Kingsley
They are attached to the rachis by a very short and slender stalk.Beautiful Ferns|Daniel Cady Eaton
Having two to many distinct blades on a common leafstalk or rachis.Handbook of the Trees of New England|Lorin Low Dame
The wing along the rachis formed by the basal segments of the pinn seems to me more conspicuous in the latter than in the former.How to Know the Ferns|Frances Theodora Parsons