As soon as I heard that the 5th edition of The American Heritage Dictionary of the English Language (AHD) had come out, I rushed to the nearest Barnes & Noble bookstore (yes, they still exist — that was Borders that closed) and plunked down two Bens (hundred dollar bills) to buy three copies at $60 each: one for my office at Penn, one for my study at home, and one for a friend. The 5th ed. was actually published in November, 2011, but I was in China then, and didn't get a chance to buy my own copies until the day I arrived back on American soil.
I own at least one copy of each of the five editions of AHD; in most cases, I own multiple copies and all the available formats. In fact you could say that I'm an "AHD kòng 控 / otaku" ("AHD obsessive"). If it didn't sound too weird, I'd say that I'm in love with the AHD, but it does sound weird, so I won't admit that. But I will confess that AHD, from the first edition, has always been my "number one" reference work and, if I were going to be exiled to Xinjiang or Siberia or marooned on a desert island, the one book, indeed, the single belonging that I would want to take with me, would — without any hesitation whatsoever — be the AHD.
All right, since everybody is probably thinking that Mair has become touched in the head, I'd better explain myself a bit. After all, I do have my reasons for being so enamored of the AHD. First and foremost is "Appendix I: Indo-European Roots". Whoever initially got the idea to include this appendix is a genius; we are all forever in their debt. Second is "Appendix II: Semitic Roots", which I think first appeared in the 4th edition. The third reason is that the essentials of the precious data in appendices I and II are incorporated into the etymologies for the main entries and in separate word histories. The fourth reason is the careful attention paid to the evolution of the alphabet, both at the beginning of each letter and in an excellent table (on p. 51 of AHD5). The list of my reasons for worshipping the AHD could be extended indefinitely: the brilliant chart of Indo-European languages on the endpapers, the 4,000+ full-color illustrations, the up-to-date vocabulary, the superb usage notes, the splendid essays on Indo-European and Proto-Semitic language and culture respectively by Calvert Watkins and John Huehnergard, and so forth.
As a Sinologist, however, I am particularly indebted to the AHD for taking Chinese and other East Asian languages seriously and doing such a good job with them. Much of the credit for this goes to Senior Lexicographer, Patrick Taylor, with whom I engaged in extensive discussion during the decade of editing that went into the making of the 5th edition. Our correspondence was occasioned by the fact that I was delighted by the inclusion of a word that I had coined in the 4th edition, namely, "topolect", but disappointed that the definition given was not what I had intended. On p. 1822a of the 4th edition, we find this definition: "A set of similar dialects constituting any of the larger distinct regional varieties of a language. For example, Mandarin Chinese is a topolect that includes the dialects of Beijing and Nanjing, and is distinct from Hakka, another topolect of Chinese." Unfortunately, this definition signifies essentially what Chinese linguists mean by dà fāngyán 大方言 ("large / major topolect"), whereas what I had intended was simply no more and no less than what the Chinese mean by fāngyán 方言 ("speech form of a place", i.e., "topolect" — whether large or small). I maintain that "dialect" is a serious mistranslation of fāngyán 方言, one that has wreaked endless havoc in linguistic analysis of Sinitic languages. In a forthcoming paper that will appear in the Festschrift for Alain Peyraube, I explain in detail what is wrong with the mistaken equation of fāngyán 方言 and "dialect", and propose alternative renderings.
I should also note that the outstanding coverage of East Asian languages in AHD5 in general owes much to Zev Handel, who was the Etymology Consultant for Chinese and Other East Asian Languages.
I think that I probably first used the word "topolect" in writing in What Is a Chinese “Dialect/Topolect”? Reflections on Some Key Sino-English Linguistic Terms (Also available as a 2.2 MB PDF.), Sino-Platonic Papers, 29 (September, 1991), 1-31, though I had been using the term in lectures already during the previous decade.
In AHD5, "topolect" is now defined thus:
The language or speech of a particular place, such as a country, region, village, or valley, especially: a. Any of the Sinitic languages, such as Mandarin or Cantonese. b. Any of the regional and local varieties of one of the Sinitic languages, such [as] one of the dialects of Mandarin.
I am satisfied with this definition.
A couple of years ago, the editors of the Oxford English Dictionary informed me that they were going to include "topolect" in the OED. I am interested in seeing how they define it. No matter how it turns out, I'm grateful to AHD4 for making topolect a matter of record and AHD5 for defining it correctly and integrating it in their treatment of Sinitic languages as a whole.