Wiktionary
whereunder
adv. (context archaic English) Under which or what.
Usage examples of "whereunder".
Pietro and the damsel, finding no more convenient refuge, betook them to an old, and all but ruinous, and now deserted, cottage, which, however, still had a bit of roof left, whereunder they both took their stand in such close quarters, owing to the exiguity of the shelter, that they perforce touched one another.