Synonyms for Precedency (same or very similar meaning)
WordNet sense 1 (status established in order of importance or urgency):
precedence, priorityWordNet sense 2 (preceding in time):
antecedence, antecedency, anteriorityWordNet sense 3 (the act of preceding in time or order or rank (as in a ceremony)):
precessionFrom the ODE community, based on WordNetadd/edit