Ra"dix (rā"dĭks), *n.*;
*pl.* L. **Radices**
(răd"ĭ*sēz), E. **Radixes**
(rā"dĭks*ĕz). [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.