403: mr. and mrs. Jan 15, 2016

Mr. and Mrs. are thought of as abbreviations for ‘mister’ and ‘missus’. Although this is how people speak today, those are not the true origins of the abbreviation. 'Mr.' is short for 'master' and 'Mrs.' is an abbreviation of 'mistress'. The change from 'master' and 'mistress' is a result of changes in speech and pronunciation at the early days of Modern English, similar to the simplification of "ma'am" from "madam".