Word Meanings - RADII - Book Publishers vocabulary database

pl. of Radius.

RADIUS VECTOR
A straight 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,
RADIUS
A right line drawn or extending from the center of a circle to the periphery; the semidiameter of a circle or sphere.
HYPORADIUS
One of the barbs of the hypoptilum, or aftershaft of a feather. See Feather.