See Also: Rachis(medicine)
rachis(dictionary)

rachis (iou)



rachis noun. . L18.
[mod. Latin, from Greek rhakhis, rhakios spine, ridge, etc.: pl. by false analogy with cuspis, iris, etc.]
Botany. The main axis of a compound leaf (esp. the frond of a fern) or of an inflorescence. L18.
Anatomy. The vertebral column, or the primitive cord from which it develops. rare. M19.
b. Zoology. The axial part of the odontophore of a mollusc. M19.
Ornithology. The shaft of a feather, esp. the part bearing the vanes. L19.
rachial adjective (chiefly Botany) of, pertaining to, or having a rachis M19.
ra'chidial adjective rachial, rachidian; Medicine spinal: E20.
ra'chidian adjective (chiefly Zoology) of or pertaining to a rachis M19.