Definition of "Elizabeth" :

noun: Queen of England from 1558 to 1603; daughter of Henry VIII and Anne Boleyn; she succeeded Mary I (who was a Catholic) and restored Protestantism to England; during her reign Mary Queen of Scots was executed and the Spanish Armada was defeated; her reign was marked by prosperity and literary genius (1533-1603)

noun: daughter of George VI who became the Queen of England and Northern Ireland in 1952 on the death of her father (1926-)

"Elizabeth II is the head of state in Great Britain."