from
The Collaborative International Dictionary of English v.0.48
Parabola \Pa*rab"o*la\, n.; pl. {Parabolas}. [NL., fr. Gr. ?; --
so called because its axis is parallel to the side of the
cone. See {Parable}, and cf. {Parabole}.] (Geom.)
(a) A kind of curve; one of the conic sections formed by the
intersection of the surface of a cone with a plane
parallel to one of its sides. It is a curve, any point of
which is equally distant from a fixed point, called the
focus, and a fixed straight line, called the directrix.
See {Focus}.
(b) One of a group of curves defined by the equation y =
ax^{n} where n is a positive whole number or a positive
fraction. For the {cubical parabola} n = 3; for the
{semicubical parabola} n = 3/2. See under {Cubical}, and
{Semicubical}. The parabolas have infinite branches, but
no rectilineal asymptotes.
[1913 Webster]
from
The Collaborative International Dictionary of English v.0.48
Cubic \Cu"bic\ (k?"b?k), Cubical \Cu"bic*al\ (-b?-kal), a. [L.
cubicus, Gr. ?????: cf. F. cubique. See {Cube}.]
1. Having the form or properties of a cube; contained, or
capable of being contained, in a cube.
[1913 Webster]
2. (Crystallog.) Isometric or monometric; as, cubic cleavage.
See {Crystallization}.
[1913 Webster]
{Cubic equation}, an equation in which the highest power of
the unknown quantity is a cube.
{Cubic foot}, a volume equivalent to a cubical solid which
measures a foot in each of its dimensions.
{Cubic number}, a number produced by multiplying a number
into itself, and that product again by the same number.
See {Cube}.
{Cubical parabola} (Geom.), two curves of the third degree,
one plane, and one on space of three dimensions.
[1913 Webster]