A skilled lexicographer draws on her Atlantic Monthly column about the latest words to present a vocabulary for the fin de siäcle. What's the word for ``sexual activity conducted interactively in cyberspace''? It's teledildonics, states Soukhanov, executive editor of the 3rd edition of The American Heritage Dictionary. She precisely defines this and hundreds of other neologisms, doggedly sniffing out their lexical sources (mahosker ``just may be of Irish or Yiddish origin or of both''). The euphemisms, acronyms, homographs, portmanteaus, and in-your-face babble used by the hippest bumbos, quant jocks, and airy-fairy boy toys from Edge City to Club Fed are laid bare before us. More rap than music, these words may be emblematic of our society at the end of the 20th century; they speak of our values. Our obsession with health, for instance, has led to a proliferation of specialties, such as emporiatrics (travel-related diseases), and emphasis on gender roles to use of the word wife as a verb. Some of the coinages, like informate, narcokleptocracy, and schmooseoisie, have a leaden ring, and their continued currency seems dubious. A few others (morph, glass ceiling) may have already buzzed their way into our lexicon for good. Most, though, are surely nonce words, trendy and ephemeral. And most, to add to the fun, are not self-explanatory-- or as the author puts it in the case of a verb compound, ``its unitary meaning cannot be deduced from the meanings of each of its constituent elements.'' Along with her evident professionalism, Soukhanov can sling the slang and pitch the kitsch with enough gusto to entertain any reader interested in the morass of new lingo that defines our lives. A detailed investigation of some loose words--most not yet entombed (so to speak) in dictionaries--by a pro who talks the talk.