(1) - Wherein (adv.) In what; -- used interrogatively. (2) - Wherein (adv.) In which; in which place, thing, time, respect, or the like; -- used relatively.
(1) - Whereon (adv.) On what; -- used interrogatively; as, whereon do we stand? (2) - Whereon (adv.) On which; -- used relatively; as, the earth whereon we live.