What Does It Mean?

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From our dictionary:
an•te•ced•ent

(an"tu•sEd'nt),
adj.
preceding; prior: an antecedent event.

n.
1. a preceding circumstance, event, object, style, phenomenon, etc.
2. antecedents,
a. ancestors.
b. the history, events, characteristics, etc., of one's earlier life: Little is known about his birth and antecedents.
3. Gram.a word, phrase, or clause, usually a substantive, that is replaced by a pronoun or other substitute later, or occasionally earlier, in the same or in another, usually subsequent, sentence. In Jane lost a glove and she can't find it, Jane is the antecedent of she and glove is the antecedent of it.
4. Math.
a. the first term of a ratio; the first or third term of a proportion.
b. the first of two vectors in a dyad.
5. Logic.the conditional element in a proposition, as "Caesar conquered Gaul," in "If Caesar conquered Gaul, he was a great general."