The Collaborative International Dictionary
Superadvenient
Superadvenient \Su`per*ad*ven"ient\, a. Coming upon; coming in addition to, or in assistance of, something. [R.]
He has done bravely by the superadvenient assistance of
his God.
--Dr. H. More.
Wiktionary
superadvenient
a. 1 come upon; coming to the increase or assistance of something. 2 Coming unexpectedly.