Words often have petrified within them whole chapters of history, literature, orthography, etymology or philology. So simple a word as “parson,” for instance, carries with it a number of valuable hints as to history, etymology, orthoepy and the like. In the time of Chaucer, who wrote “The Persone's Tale,” it was spelled with an e. The e before r was first pronounced as in “parson,” and then the word was spelled with an a, this tendency being illustrated in the pronunciation of such names as “Berkley” and “Derby,” and the spelling of “Clark,” which is, of course, derived from “clerk.” The word “person” comes from the Latin persona, which was originally used for the masks worn by the characters of a play and then was applied to the characters themselves—personæ dramatis. It was derived from personare, “to sound through and through,” because the player's voice sounded through the mask, which was so constructed as to increase the apparent volume of sound. From a character in a play persona came to mean a character in life, an individual; and then, in the Middle Ages, the ecclesiastical representative of a parish was first called the “person” and later the “parson” of the village.
FOSSIL MEDICAL WORDS. JAMA. 2012;307(5):437. doi:10.1001/jama.2012.17