Placidus

Placidus is Latin for "placid, gentle, quiet, still, calm, mild, peaceful" and can refer to:


 * Placidus (martyr), 4th-century Sicilian martyr
 * Lactantius Placidus (c. 350 – c. 400), writer
 * Flavius Arcadius Placidus Magnus Felix (480–511), Consul of Rome
 * Saint Placidus (6th century), follower of Benedict of Nursia
 * Placidus de Titis (also de Titus, Latinization of Placido de Titi, 1603–1668), astrologer
 * Placidus Böcken (1690–1752), German Benedictine canon lawyer, Vice-Chancellor of the University of Salzburg
 * Placidus Braun (1756–1829), Bavarian Benedictine priest, historian and archivist
 * Placidus Fixlmillner (1721–1791), Benedictine priest, first astronomer to compute the orbit of Uranus
 * Placidus Nkalanga (1919–2015), Tanzanian Prelate of Roman Catholic Church
 * Placidus a Spescha (1752–1833), Swiss monk and Alpine explorer