Whereof

Part of speech: adverb (adv.)

1. Of which; of whom; formerly, also, with which; -- used relatively. I do not find the certain numbers whereof their armies did consist. Sir J. Davies. Let it work like Borgias' wine, Whereof his sire, the pope, was poisoned. Marlowe. Edward's seven sons, whereof thyself art one. Shak.

2. Of what; -- used interrogatively. Whereof was the house built Johnson.