Our online medical glossary of medical terms and definitions includes definitions for terms related to treatment, and general medicine
RHACHIS
Origin: See Rachis
Alternative forms: rechis.
1. The spine.
2. The continued stem or midrib of a pinnately compound leaf, as in a roseleaf or a fern. The principal axis in a raceme, spike, panicle, or corymb.
3. The shaft of a feather. The rhachis of the after-shaft, or plumule, is called the hyporhachis. The central cord in the stem of a crinoid.
The medianpart of the radula of a mollusk.
A central cord of the ovary of nematodes.
Source: Websters Vocabulary