Petrus

Petrus comes from the Greek meaning "rock", and is the common English prefix "petro-" used to describe rock-based substances, like petros-oleum or "rock oil." As the source of Peter, it is a common name for people from antiquity through the medieval era, and may refer to one of the following:

As a name:
* Petrus, Saint Peter, the first pope
* Priest Petrus, 5th century Illyrian priest
* Petrus Abailardus, Latin name for Peter Abelard
* Petrus Alfonsus, Spanish Jewish writer
* Petrus Aureolus
* Petrus Baldus de Ubaldis
* Petrus Bernardinus, Florentine sectarian
* Petrus Canisius, 16th century German Catholic theologian and polemicist
* Petrus Capuanus or Peter of Capua, an Italian scholastic
* Petrus Christus, (ca. 1410/1420 - ca. 1475/76), Dutch painter
* Petrus de Abano or Pietro d'Abano (1257 – 1315) Italian philosopher and doctor
* Petrus de Amalfia, 14th century Italian music theorist
* Petrus de Cruce, late 13th century composer and author, one of the most significant and influential composers of the late ars antiqua
* Petrus de Natalibus, Venetian hagiographer
* Petrus de Picardia, 13th century French music theorist
* Petrus de Sancto Dionysio, 14th century French music theorist
* Petrus Diaconus, several people
* Petrus frater dictus Palma ociosa, 14th century French music theorist, one of the first to illustrate current musical innovations
* Petrus Jacobus Joubert
* Petrus Le Viser, late 13th century musician, important in the history of tempo and rhythm
* Petrus optimus notator, 13th century musical scribe in Paris, important for notating Notre Dame polyphony
* Petrus Peregrinus = Peter de Maricourt, 13th century French writer on magnetism and astrolabes
* Petrus Ramus
* Petrus Trothun Aurelianis, 13th century singer of the Notre Dame School

Other:
* Château Pétrus, a Pomerol Bordeaux wine producer