An earl has the title Earl of [X] when the title originates from a placename, or Earl [X] when the title comes from a surname. In either case, he is referred to as Lord [X], and his wife as Lady [X].
There is no female styling of “earl,” and, because the rank corresponds to the French comte or German Graf (count), a woman who holds the rank, or the wife of an earl, is styled “countess.”
Historically, an earl was the ruler of a county or earldom, but the title is now primarily ceremonial. In the U.K., there are currently around 190 earls. The Earl of Wessex is the highest-ranking earl in the peerage system. He’s also second in line to the British throne.
Britain's peerage system, which dates to Anglo-Saxon times, consists of five ranks: duke, marquess, earl, viscount and baron, according to Debrett's, a leading source of information on the British peerage system.
Known as the peerage system, this noble hierarchy consists of five ranks today: duke, marquess, earl, viscount, and baron. The title of earl — the oldest in the peerage system — dates back to the end of the early medieval period, during the reign of King Canute (or Cnut) in the 11th century.
The meaning of EARL is a member of the British peerage ranking below a marquess and above a viscount.
When a duke or a marquess has an earldom as his second title, this is ‘by courtesy’ given to his eldest son: thus the heir of the Duke of Northumberland is Earl Percy while that of the Marquess of Winchester is the Earl of Wiltshire.