from
The Collaborative International Dictionary of English v.0.48
Parabolic \Par`a*bol"ic\, Parabolical \Par`a*bol"ic*al\, a. [Gr.
paraboliko`s figurative: cf. F. parabolique. See {Parable}.]
[1913 Webster]
1. Of the nature of a parable; expressed by a parable or
figure; allegorical; as, parabolical instruction.
[1913 Webster]
2. [From {Parabola}.] (Geom.)
(a) Having the form or nature of a parabola; pertaining
to, or resembling, a parabola; as, a parabolic curve.
(b) Having a form like that generated by the revolution of
a parabola, or by a line that moves on a parabola as a
directing curve; as, a parabolic conoid; a parabolic
reflector; a parabolic antenna.
[1913 Webster +PJC]
{Parabolic conoid}, a paraboloid; a conoid whose directing
curve is a parabola. See {Conoid}.
{Parabolic mirror} (Opt.), a mirror having a paraboloidal
surface which gives for parallel rays (as those from very
distant objects) images free from aberration. It is used
in reflecting telescopes.
{Parabolic spindle}, the solid generated by revolving the
portion of a parabola cut off by a line drawn at right
angles to the axis of the curve, about that line as an
axis.
{Parabolic spiral}, a spiral curve conceived to be formed by
the periphery of a semiparabola when its axis is wrapped
about a circle; also, any other spiral curve having an
analogy to the parabola.
[1913 Webster]