2. [syn: precession, precedence, precedency]
The Collaborative International Dictionary of English v.0.48:
Precession \Pre*ces"sion\, n. [L. praecedere, praecessum, to go
before: cf. F. pr['e]cession. See Precede.]
The act of going before, or forward.
Lunisolar precession. (Astron.) See under Lunisolar.
Planetary precession, that part of the precession of the
equinoxes which depends on the action of the planets
Precession of the equinoxes (Astron.), the slow backward
motion of the equinoctial points along the ecliptic, at
the rate of 50.2[sec] annually, caused by the action of
the sun, moon, and planets, upon the protuberant matter
about the earth's equator, in connection with its diurnal
rotation; -- so called because either equinox, owing to
its westerly motion, comes to the meridian sooner each day
than the point it would have occupied without the motion
of precession, and thus precedes that point continually
with reference to the time of transit and motion.
WordNet (r) 3.0 (2006):
n 1: the motion of a spinning body (as a top) in which it
wobbles so that the axis of rotation sweeps out a cone
2: the act of preceding in time or order or rank (as in a
ceremony) [syn: precession, precedence, precedency]