2. (Bot.) (a) The continued stem or midrib of a pinnately compound leaf, as in a rose leaf or a fern. (b) The principal axis in a raceme, spike, panicle, or corymb.

3. (Zoöl.) (a) The shaft of a feather. The rhachis of the after-shaft, or plumule, is called the hyporhachis. (b) The central cord in the stem of a crinoid. (c) The median part of the radula of a mollusk. (d) A central cord of the ovary of nematodes.

RHACHITIS
Rha*chi"tis, n. Etym: [NL.]

Defn: See Rachitis.

RHADAMANTHINE
Rhad`a*man"thine, a.

Defn: Of or pertaining to Rhadamanthus; rigorously just; as, a
Rhadamanthine judgment.

RHADAMANTHUS; RHADAMANTHYS
Rhad`a*man"thus, Rhad`a*man"thys, n. Etym: [L., fr. Gr. (Greek
Mythol.)

Defn: One of the three judges of the internal regions; figuratively, a strictly just judge.

RHAETIAN
Rhae"ti*an, a & n.

Defn: Rhetian.