''Misogynist'', as an English word meaning women hater, has been around for at least 400 years, although the first lexicographer to note it, Thomas Blount in 1656, softened it slightly to say that it referred to one with hatred for, or contempt for, women. Every first-rate dictionary since has put the stress on hatred, with a hint of pathological phobia rather than mere dislike or disregard.

For some, that is the end of the matter. Words, once defined, are to be treated as if acts of Parliament, and their meaning, once fixed, can neither be altered nor repealed, least of all by the ignorant.

Alas, there is no dictionary maker in the world who does not concede that the meaning of words comes to change over time. Some words gather fresh meanings, others lose meanings they once had. Some words are chronically misused, and by such regular misuse come in time to mean something quite different from the original strict dictionary meaning.

Thus the word ''fulsome'', which, strictly, means something foul, smelly and completely distasteful, as something from an open sewer. It was originally ''foulsome''. It came to have a second meaning of ''cloying, insincere and flattering'' and one giving ''fulsome praise'' originally was one laying on fake absurd compliments with a trowel. But chronic misuse by people such as John Howard, who seemed to think that it meant ''generous'', has had its effect.

As a result, the general meaning of fulsome is now recognised by the more descriptive dictionaries to be almost exactly the opposite of the original meaning. It is probably no longer wrong to use it in this way, though no educated person would, of course.

Likewise with ''enormity'', which did not originally mean ''enormousness'' but ''wickedness'', ''decimate'', which originally meant to kill one in every 10 but now may mean ''to kill a great number, perhaps nine in every 10''. Other words under great pressure are ''refute'' which, strictly, means to ''prove wrong, with facts and arguments'' but, which common usage suggests to mean little more than ''to contradict, dispute or deny''.

Other words gain or lose meaning because of a changing society. Some pedants believe, wrongly, that there was once a difference between ''programme'' and ''program'' and that, except in relation to computers, the former is correct. In fact, program has been around for much longer than the poncified ''programme'', although it been only in recent times that either has become a verb.

My long 16-volume Oxford English Dictionary (published 1933) does not contain the word ''sexist'', or any variation referring to discrimination by gender. It is, in short, a new concept. ''Sexism'' existed, but without reference to being sexist. It was defined as being an obsolete Old French term, derived from sixieme, meaning a (musical) sixth, or a run or sequence of six cards.

Does misogyny now mean ''entrenched prejudice against women''? As opposed to the pathological hatred that a lexicographer might have insisted upon 50 years ago?

Perhaps. But I expect Ms Butler is ahead of the crowd with this. The Macquarie often is, which is one reason it struggles for authority among purists. Its sin is not so much that it is ''descriptivist'', describing what people actually say and mean, rather than ''prescriptivist'', recording what words ''ought to mean''. Every dictionary is, at the end of the day, descriptivist, and every dictionary more than a year old is, to an extent, out of date. But some lexicographers, following word herds, note and acknowledge shifts in meaning; others, such as Ms Butler, wheel with the headers, race on the wing, where the best and boldest riders take their place. They are first to notice, and, sometimes, as with quantum theory, their very act of noticing causes the change.

That's why the Macquarie is fashionable, but not authoritative.

It will be a while yet before I personally dilute the vitriol in misogyny.