Radius vector *to* Raid

**Radius vector**

(||Ra"di*us vec"tor)

**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.

**Radix**

(Ra"dix) *n.*; *pl.* L. **Radices** E. **Radixes** [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.

**Radula**

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

**Raduliform**

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

**Raff**

(Raff) *v. t.* [*imp. & p. p.* Raffed (raft); *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**

(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.