October has had many identity crises. Although originally, as its name implies, it was the eighth month of the old Roman year, late in the first century AD it became Domitianus. The change was introduced by the Emperor Domitian, who was no doubt conscious that his most illustrious predecessors, Augustus and Julius Caesar, had had months named in their honour.
But the new name did not long survive Domitian's death in AD96. Forty years later, the Emperor Antonius Pius was more subtle: he renamed the month Faustinus, after his wife Faustina. And towards the end of the second century AD, October was again renamed Invictus, "the unconquered", this time the allusion being, we are told, to the athletic prowess of the latest emperor, Commodus.
But for most of the past 2,000 years or so, it has been plain October. It retained its name even when it became our tenth month, when New Year's Day reverted from March 1st to January. In this respect, the Norsemen got it right, calling October Teomonath, "tenth month".
Call it what you will, but this month marks a turning of the year: it is colder, wetter, darker and windier than its predecessors, and a stern reminder to us of the rigours of approaching winter.
The temperature on an average October day rises to a mere 13 or 14 Celsius, three or four degrees less than the September norm. Only very rarely does the temperature exceed 20, and only once since records began in Ireland has it touched 25 Celsius. Few of us will remember the occasion: it was 90 years ago, on October 3rd, 1908.
Ground frost, at the other extreme, occurs on five or six of October's 31 days. Very occasionally, even the air temperature falls below zero, an occurrence almost unheard of in September.
About every 10 years or so, a little snow may fall, but it tends to melt as soon as it touches ground and rarely causes trouble. The waters around our coasts, too, are becoming colder: the usual sea temperature is about 12 or 13 degrees, compared to the August peak of 15 or 16 Celsius.
There is less sun in October than in the preceding month, if for no other reason than that the days are significantly shorter. The average September day has some four or five hours of sunshine: the October average is only three.
And we can expect it to become more windy - not as blustery, perhaps, as November or December, but windy enough to produce gales on four or five days of the month along our western and northern coasts.