Part 15

2. (Anat.) The preaxial bone of the forearm, or brachium, corresponding to the tibia of the hind limb. See Illust. of Artiodactyla.

The radius is on the same side of the limb as the thumb, or pollex, and in man it is so articulated that its lower end is capable of partial rotation about the ulna.

3. (Bot.) A ray, or outer floret, of the capitulum of such plants as the sunflower and the daisy. See Ray, 2.

4. pl. (Zoöl.) (a) The barbs of a perfect feather. (b) Radiating organs, or color-markings, of the radiates.

5. The movable limb of a sextant or other angular instrument. Knight.

Radius bar (Mach.), a bar pivoted at one end, about which it swings, and having its other end attached to a piece which it causes to move in a circular arc. -- Radius of curvature. See under Curvature.

||Ra"di*us vec"tor (vk"tr). 1. (Math.) A straight line (or the length ||of such line) connecting any point, as of a curve, with a fixed ||point, or pole, round which the straight line turns, and to which it ||serves to refer the successive points of a curve, in a system of ||polar coördinates. See Coördinate, n.

2. (Astron.) An ideal straight line joining the center of an attracting body with that of a body describing an orbit around it, as a line joining the sun and a planet or comet, or a planet and its satellite.

Ra"dix (r"dks), n.; pl. L. Radices (rd"*sz), E. Radixes (r"dks*z). [L. radix, -icis, root. See Radish.] 1. (Philol.) A primitive word, 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.) The root of a plant.

||Rad"u*la (rd"*l), n.; pl. Radulæ (- l). [L., a scraper, fr. radere to ||scrape.] (Zoöl.) The chitinous ribbon bearing the teeth of mollusks; ||-- called also lingual ribbon, and tongue. See Odontophore.

Ra*du"li*form (r*d"l*fôrm), a. [L. radula a scraper + -form.] Rasplike; as, raduliform teeth.

Raff (rf), v. t. [imp. & p. p. Raffed (rft); p. pr. & vb. n. Raffing.] [OF. raffer, of German origin; cf. G. raffen; akin to E. rap to snatch. See Rap, and cf. Riffraff, Rip to tear.] To sweep, snatch, draw, or huddle together; to take by a promiscuous sweep. [Obs.]

Causes and effects which I thus raff up together.

Carew.

Raff, n. 1. A promiscuous heap; a jumble; a large quantity; lumber; refuse. "A raff of errors." Barrow.

2. The sweepings of society; the rabble; the mob; -- chiefly used in the compound or duplicate, riffraff.

3. A low fellow; a churl.

Raff merchant, a dealer in lumber and odd refuse. [Prov. Eng.]

Raf`fa*el*esque" (rf`f*l*sk"), a. Raphaelesque.

Raf"fi*a (rf"f*), n. (Bot.) A fibrous material used for tying plants, said to come from the leaves of a palm tree of the genus Raphia. J. Smith (Dict. Econ. Plants).

Raf"fi*nose` (rf"f*ns`), n. [F. raffiner to refine.] (Chem.) A colorless crystalline slightly sweet substance obtained from the molasses of the sugar beet.

Raff"ish (rf"sh), a. Resembling, or having the character of, raff, or a raff; worthless; low.

A sad, raffish, disreputable character.

Thackeray.

Raf"fle (rf"f'l), n. [F. rafle; faire rafle to sweep stakes, fr. rafler to carry or sweep away, rafler tout to sweep stakes; of German origin; cf. G. raffeln to snatch up, to rake. See Raff, v.] 1. A kind of lottery, in which several persons pay, in shares, the value of something put up as a stake, and then determine by chance (as by casting dice) which one of them shall become the sole possessor.

2. A game of dice in which he who threw three alike won all the stakes. [Obs.] Cotgrave.