chronogramThe capitals MDCIII correspond to 1603, the year of Queen Elizabeth I's death.
chron·o·gram
C0340800 (krŏn′ə-grăm′, krō′nə-)n.1. The record produced by a chronograph.2. An inscribed phrase in which certain letters can be read as Roman numerals indicating a specific date.chron′o·gram·mat′ic(-grə-măt′ĭk) adj.chron′o·gram·mat′i·cal·ly adv.