(historical) The Russian state from 1721 to 1917.

plural of empirical formula

(historical) The German state which existed, with Berlin as its capital, between 1871 and 1918.

(historical) The empire ruled by the Achaemenid dynasty 550–330 B.C.E.. / (historical) The empire ruled by the Sassanid dynasty 224–651 C.E..

(historical) The empire which succeeded the Roman Republic and existed between 27 B.C.E. and 476 C.E. in the west (and until 1453 C.E. in the east; see Byzantine Empire), encompassing territories stretching from Britain and Germany to Spain, North Africa and the Persian Gulf.

(chemistry) A notation indicating the ratios of the various elements present in a compound, without regard to the actual numbers.

(historical) A large Turkish empire which began as a Turkish sultanate centered in modern Turkey; founded in the late 13th century, it lasted until the end of World War I.

(historical) The predominantly Greek-speaking continuation of the Roman Empire during Late Antiquity and the Middle Ages with its capital city being Constantinople (modern-day Istanbul), originally known as Byzantium, which fell in 1453.

(chiefly historical) The United Kingdom and its overseas dependencies and colonies.

Data derived from reliable measurement or observation.