Synonyms for Precedent (same or very similar meaning)
WordNet sense 1 (a system of jurisprudence based on judicial precedents rather than statutory laws):
common law, case law
WordNet sense 2 (an example that is used to justify similar occurrences at a later time):
case in point
WordNet sense 3 (existing or coming before):
preceding
From the ODE community, based on WordNet
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