"Synodical" is a word in ENGLISH

Pertaining to conjunction, especially to the period
between two successive conjunctions; extending from one conjunction, as
of the moon or a planet with the sun, to the next; as, a synodical
month (see Lunar month, under Month); the synodical revolution of the
moon or a planet.

Of or pertaining to a synod; transacted in, or
authorized by, a synod; as, synodical proceedings or forms.