etymology (n.) Look up etymology at Dictionary.com
late 14c., ethimolegia "facts of the origin and development of a word," from Old French et(h)imologie (14c., Modern French étymologie), from Latin etymologia, from Greek etymologia, properly "study of the true sense (of a word)," from etymon "true sense" (neuter of etymos "true, real, actual," related to eteos "true") + -logia "study of, a speaking of" (see -logy). Latinized by Cicero as veriloquium.

In classical times, of meanings; later, of histories. Classical etymologists, Christian and pagan, based their explanations on allegory and guesswork, lacking historical records as well as the scientific method to analyze them, and the discipline fell into disrepute that lasted a millennium. Flaubert ["Dictionary of Received Ideas"] perhaps had them in mind when he wrote that the general view was that etymology was "the easiest thing in the world with the help of Latin and a little ingenuity." As a modern branch of linguistic science, from 1640s. Related: Etymological; etymologically.