precession vs precedence

precession and precedence both are nouns.

Word	Noun	Adjective	Verb	Adverb
precession	Yes	No	No	No
precedence	Yes	No	No	No

As nouns, precession and precedence are synonyms defined as:

precession and precedence: the act of preceding in time or order or rank (as in a ceremony)

Other synonyms of precession include precedency.

precession (noun)	precedence (noun)
the act of preceding in time or order or rank (as in a ceremony)	the act of preceding in time or order or rank (as in a ceremony)
the motion of a spinning body (as a top) in which it wobbles so that the axis of rotation sweeps out a cone	preceding in time
	status established in order of importance or urgency