Mr.

Mister, usually written in its contracted form Mr. (American and Canadian English) or Mr (British English, Australian English and New Zealand English), is a commonly used English honorific for men without a higher honorific, professional title, or any of various designations of office. The title Mr derived from earlier forms of master, as the equivalent female titles Mrs, Miss, and Ms all derived from earlier forms of mistress. Master is sometimes still used as an honorific for boys and young men.

The plural form is Messrs(.), derived from the French title messieurs in the 18th century. Messieurs is the plural of monsieur (originally mon sieur, "my lord"), formed by declining both of its constituent parts separately.

Historical etiquette

Historically, mister was applied only to those above one's own status if they had no higher title such as Sir or my lord in the English class system. That understanding is now obsolete, as it was gradually expanded as a mark of respect to those of equal status and then to all men without a higher style.

In the 19th century and earlier in Britain, two gradations of "gentleman" were recognised; the higher was entitled to use "esquire" (usually abbreviated to Esq, which followed the name), and the lower employed "Mr" before the name. Today, on correspondence from Buckingham Palace, a man who is a UK citizen is addressed with post-nominal "Esq.", and a man of foreign nationality is addressed with prefix "Mr".