American Dictionary of the English Language

AN'TEDATE, noun [Infra.] Prior date; a date antecedent to another.

AN'TEDATE, verb transitive [Latin ante, and datum, given. See Date.]

1. To date before the true time; thus, to antedate a deed or a bond is to express a date anterior to the true time of its execution.

2. To anticipate; to take before the true time.

And antedate the bliss above.