History and etiquette tell us that Mister and Missus, known by the contractions Mr. and Mrs., are the proper form of address for men and women. Beneath the surface of these everyday honorifics lies a linguistic glitch that has spawned social havoc since “Mrs.” entered mainstream English in the 17th century.
Mister is a direct variant of master, which in turn derives from the Old English maegester meaning “one having control or authority.” Already a discrepancy rears its head: The period that follows the abbreviation Mr. is usually omitted in British English grammar. According to the Oxford A-Z of Grammar and Punctuation, “If the abbreviation includes both the first and last letter of the abbreviated word, as in ‘mister’ and ‘doctor’, a full stop is not used.” However, a period always follows the title in American English grammar – as in Mr. President and Mr. Speaker.
