Kenneth G. Wilson (1923–). The Columbia Guide to Standard American English. 1993.
classic (adj., n.), classical (adj.)
In some of their senses these are synonymous, but in others they are distinctive: A classical profile means much the same as a classic profile, one based on the norms of ancient Greek and Roman statuary. Artifacts whose reputations stay bright over the centuries, are classic—as in cars—and classical—as in music. Sometimes, though, classical music simply means “serious music,” as contrasted with popular music; in that sense, a piece of classical music could be only a few hours old. The Iliad and The Aeneid are classical literature, and they are also classics. Indeed, all the art and literature of the Greeks and Romans is classical (because that is the period of origin), but as individual pieces only the best among them are classics “for all time.” The classical languages are still Greek and Latin.
