If you can tell the history of the world in 100 objects, as the British Museum's Neil MacGregor did in 2010, then it ought to be possible to tell the history of a language in a similar number. But, as with objects, it isn't enough for each word to be interesting in its own right. It has to tell a story. And each of these individual stories should add up to the history of the English language as a whole.
I needed principles on which to base my selection. The obvious one is chronological. The history of English is traditionally divided into periods: Old English, from the arrival of the Anglo-Saxons in 449 AD until the 11th century; Middle English from then until the 15th century; Early Modern English from then until the 18th century; and Modern English thereafter. It's important to choose words that show the passage of time in this way, and give us a real insight into social history.
But, at any one time, English is a kaleidoscope of styles, genres, and dialects. In particular, the words we use when we speak aren't the same as those we use when we write. Far more people speak a nonstandard variety of English than speak standard English, and their story must be told too. Nor must we neglect the commonest everyday words, such as slang, cant, and taboo words. There can't be any pussy-footing, if you're a serious linguist. The rude words are just as much a part of our linguistic history.
Professional words, such as those associated with the law, medicine, religion, and academia, provide another historical strand. Of the million+ words in English, three-quarters belong to the various domains of science and technology. And the global spread of English has to be represented. Around a third of the world's population use English now, and one of the consequences has been the emergence of international dialects, each with its own local vocabulary. The process started when British and American English diverged, but it has continued since with many 'new Englishes' in Australasia, the Caribbean, and Africa.
Nor must a word-book forget how words are formed. Vocabulary is a matter of word-building as well as word-using. Most words in English are built up by using prefixes and suffixes, by combining elements from different languages, or by abbreviating and compounding. And we readily make words from the names of people, places, and things. English is a playful and innovative language, whose speakers love to use their imaginations in creating new vocabulary. They delight in bending and breaking the rules when it comes to word creation.
Looking down my complete list of 100, the thing that most strikes me is their diversity - a reflection of the colorful political and cultural history of the English-speaking peoples over the centuries. English speakers from all parts of the world have used their language like a vacuum-cleaner, eagerly sucking in words from other languages whenever they find it useful to do so. If a present-day Dr Who were to travel back to 449 AD, when the first Anglo-Saxon boats arrived in Britain, his biggest problem would not be alien monsters, but getting the Anglo-Saxons to understand his alien words.
David Crystal is the author of The Story of English in 100 Words [St. Martin's Press, $22.99].