It traces through the history of
semantic drift for a lot of words and their changes in meaning. Ammon Shea has also got another book called “
Reading the O.E.D.” in which he writes about the experience and his findings of deciding to read a complete edition of the Oxford English Dictionary from start to finish where many of the findings for “Bad English” seem to have been found. He’s also now a dictionary consultant for Oxford University Press.
"…]Almost all words change their meanings. This is one of the aspects of language that is firmly established. It ought to be evident to all of us that words will take on new meanings as we generally find it confusing to read writing that is more than a few hundred years old. Many of the words carried a different significance than we give to them today…]"
In modern times people tend not to use the word Egregious to mean “remarkably good” or “awful” to express positive attributes. “Girl” is no longer used to indicate a young person irrespective of their sex. And if I use the phrase “gay guy” the first thing that comes to your mind probably is not a very happy Guy Fawkes. The language that you and I speak and write with is derived from previous forms. Those forms continue to evolve.
Changes in language is it’s own field of study and it has it’s own typology. Narrowing, widening, metonymy, synecdoche, meiosis, degeneration,and elevation are all terms for types of semantic changes that occur.
Individuals and groups make words and assign meanings. In response to this others might ignore, reject, or adopt (possibly with modifications) the term or usage. With enough popularity of a usage the word or usage ends up in dictionaries and other references. If you’d like to ignore or reject that’s fine. But that may also be the source of a communications barrier between you and others.
[Try] to read something that was written by people hundreds of years ago (try reading the original Beowulf). You might have trouble understanding English dialects from an area outside of the one in which you live. Ignoring the regional variations in word usage without your home country you’ll find that English nations outside your country will have evolved some words, phrases, and idioms differently. I’m sure some you’ll recognize and can translate without seeking references (ex: football). Some might cause confusion such as “table” (which could mean to remove an item from discussion for now, or open it up for discussion now). Others, such as “naff” will probably have no immediate meaning to you. Language changes within a culture don’t tend to be the huge problem that they’ve been rumored to be.