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adj. synodic

Pertaining to or transacted in a synod: as, synodical proceedings or forms.

In astronomy, pertaining to a conjunction or two successive conjunctions of the heavenly bodies.

"There are some twenty-eight of these churches, and they appoint their own bishops by synodical processes, and seek confirmation of the election from the Bishop of Rome."

synodical revolution of a planet    synodical month   

synodal    lockean/jeffersonian    parcel post    leadscrew    oxymoronic