Dictionary.net

An annual tax of a silver penny, formerly paid by the English to the Pope as successor of St. Peter.

An ancient levy or tax of a penny on each house throughout Eng- land, paid to the pope. It was called "Peter- pence," because collected on the day of St. Peter, ad vinculo; by the Saxons it was called "Rome-feoh," "Itome-scot," and "Rome- pennying," because collected and seut to Rome; and, lastly, it was called "hearth money," because every dwelling-house was liable to it, and every religious house, the abbey of St Albans alone excepted. Wharton.

n. An annual tax formerly paid by the English to the pope, being a penny for every house.