OBSOLETE, adj. No longer used by the timid. Said chiefly of words.
A word which some lexicographer has marked obsolete is ever thereafter
an object of dread and loathing to the fool writer, but if it is a
good word and has no exact modern equivalent equally good, it is good
enough for the good writer. Indeed, a writer's attitude toward
"obsolete" words is as true a measure of his literary ability as
anything except the character of his work. A dictionary of obsolete
and obsolescent words would not only be singularly rich in strong and
sweet parts of speech; it would add large possessions to the
vocabulary of every competent writer who might not happen to be a
competent reader.
-- Ambrose Bierce, "The Devil's Dictionary"