-ess

Usage note
Since at least the 14th century, English has both borrowed feminine nouns in -ess from French (-esse in French and in some early English forms) and applied the French ending to native or naturalized words, most frequently agent nouns in -er or -or. Some of the earliest borrowings—titles for the nobility and church dignitaries—are still in use, among them countess, princess, duchess, empress, abbess, and prioress. Of the scores of new nouns that were created from the 14th century on, many have long ago disappeared entirely from use: devouress; dwelleress. But many have survived, although their use has declined sharply in the latter half of the 20th century.
Nouns in -ess denoting occupation or profession are rapidly disappearing from American English. The fourth edition of the Dictionary of Occupational Titles (DOT), published by the U.S. Department of Labor in 1977, specifies genderless titles for thousands of occupations. Airlines now refer to cabin personnel as flight attendants, not stewards and stewardesses. In the arts, authoress, editress, poetess, sculptress, and similar terms are considered offensive by many and are almost always replaced by author, editor, poet, sculptor. Nouns in -ess designating the holder of public office are hardly ever encountered in modern American usage. Women holding the office of ambassador, mayor, or governor are referred to by those titles rather than by the older, sex-marked ambassadress, mayoress, or governess. (Governess has developed a special sense in relation to childcare; this use is less common in the U.S. than in Britain.) Among other terms almost never used in modern American English are ancestress, directress, instructress, manageress, oratress, and proprietress. If the sex of the performer is not relevant to performance of the task or function, the neutral term in -er or -or is now widely used.
Some nouns in -ess are still current: actress (but some women in the acting profession prefer to be called actors); adventuress; enchantress; heiress (largely in journalistic writing); hostess (but women who conduct radio and television programs are referred to as hosts); millionairess; murderess; postmistress (but not in official U.S. government use); seamstress; seductress; sorceress; temptress; and waitress (the DOT substitute server has not been widely adopted).
Jewess and Negress are generally considered offensive today. Mistress has given way to master in the sense of one who has acquired expertise in something: She is a master at interpreting financial reports. See also -enne, -ette, -trix.