Defn: A primitive, from which spring other words; a radical; a root; an etymon.

2. (Math.) (a) A number or quantity which is arbitrarily made the fundamental number of any system; a base. Thus, 10 is the radix, or base, of the common system of logarithms, and also of the decimal system of numeration. (b) (Alg.) A finite expression, from which a series is derived. [R.] Hutton.

3. (Bot.)

Defn: The root of a plant.

RADULA Rad"u*la, n.; pl. Radulæ. Etym: [L., a scraper, fr. radere to scrape.] (Zoöl.)

Defn: The chitinous ribbon bearing the teeth of mollusks; — called also lingual ribbon, and tongue. See Odontophore.

RADULIFORM
Ra*du"li*form, a. Etym: [L. radula a scraper + -form.]

Defn: Rasplike; as, raduliform teeth.

RAFF
Raff, v. t. [imp. & p. p. Raffed; p. pr. & vb. n. Raffing.] Etym:
[OF. raffer, of German origin; cf. G. raffen; akin to E. rap to
snatch. See Rap, and cf. Riffraff, Rip to tear.]

Defn: To sweep, snatch, draw, or huddle together; to take by a promiscuous sweep. [Obs.] Causes and effects which I thus raff up together. Carew.