Baron & Baroness

In the British peer system, barons rank below viscounts, and form the lowest rank in the peerage. A female of baronial rank has the honorific baroness. A baron may hold a barony, if the title relates originally to a feudal barony by tenure, although such tenure is now obsolete in England and any such titles are now held in gross, if they survive at all, as very few do, sometimes along with some vestigial manorial rights, or by grand serjeanty.

Viscount & Viscountess

A viscount is said to hold a "viscountship" or "viscounty", or a "viscountcy". The female equivalent of a viscount is a viscountess. The word viscount corresponds in Britain to the Anglo-Saxon shire reeve. Thus early viscounts were originally normally given their titles by the monarch, not hereditary; but soon they too tended to establish hereditary principalities lato sensu (in the wider sense).

Earl & Countess

Earls originally functioned essentially as royal governors. Though the title of Earl was nominally equal to the continental duke, unlike them earls were not de facto rulers in their own right. In the present day a number of earldoms take their names from towns, mountains, or simply surnames. Nevertheless, some consider that the earldoms named after counties retain more prestige. The English never developed a feminine form of earl; the wife of an earl is also styled countess.

Marquess & Marchioness

A woman with the rank of marquess, or the wife of a marquess, is a marchioness. In England (later Britain, ultimately the UK) the monarchy is the only authority capable of awarding hereditary titles. It managed to keep a tight grip on aristocratic titles, so the ranks of the peerage still correspond fairly neatly to the wealth of those who bear titles.

Duke & Duchess

A duke is a member of the nobility, historically of highest rank below the monarch, and historically controlling a duchy. The title comes from the Latin Dux Bellorum, which had the sense of "military commander". In the Modern Age, it remains the highest titular peerage in France, Portugal, Spain, the United Kingdom, and Italy. A woman who holds in her own right the title to such duchy or dukedom, or is the wife of a duke, is normally styled duchess.

Prince & Princess

King & Queen

A king is a head of state, who may or may not, depending on the style of government of a nation, exercise monarchal powers over a territory, usually called a kingdom or a realm. The female equivalent of king is queen. King could be a tribal leader or chief, or the tyrant of a city state. Often, the king will not only have a political function, but the same time a religious one, acting as high priest or divine king.