from
The Collaborative International Dictionary of English v.0.48
paracentric \par`a*cen"tric\ (p[a^]r`[.a]*s[e^]n"tr[i^]k),
paracentrical \par`a*cen"tric*al\
(p[a^]r`[.a]*s[e^]n"tr[i^]*kal), a. [Pref. para- + centric,
-ical: cf. F. paracentrique.]
Deviating from circularity; changing the distance from a
center.
[1913 Webster]
{Paracentric curve} (Math.), a curve having the property
that, when its plane is placed vertically, a body
descending along it, by the force of gravity, will
approach to, or recede from, a fixed point or center, by
equal distances in equal times; -- called also a
{paracentric}.
{Paracentric motion} or {Paracentric velocity}, the motion or
velocity of a revolving body, such as a planet, by which
it approaches to, or recedes from, the center, without
reference to its motion in space, or to its motion as
reckoned in any other direction.
[1913 Webster]