YOU could feel the seasons changing last weekend. A weatherfront went through, sweeping away the last balmy days of summer and leaving behind the chill air of autumn – "the season of mists and mellow fruitfulness", to use Keats' old chestnut.

Shiny new chestnuts are one of the joys of autumn – I like to dropkick a conker almost as much as I love to stand beneath a deciduous tree, poised in readiness like a wicketkeeper waiting for a snick, hoping for a gust to blow a blizzard of leaves for me to chase and catch.

Originally in Britain, this season was called harvest, an ancient word which seems to have its beginnings somehow in plucking and cropping. Autumn was a new word in English that was borrowed from French, and it had replaced harvest as the name of the season by the 16th Century, with harvest narrowing its meaning to the plucking of crops from the fields.

Those who didn't like using this French word referred to autumn as the fall, as in the fall of the leaf. It must have been quite a popular as the 17th Century colonial settlers in America took it with them. There, the "fall" stuck, whereas on our side of the pond the language evolved so that today "fall" sounds like a vulgar Americanism for good old autumn.

The star of autumn is undoubtedly the horse chestnut tree – round our way, it has been a fairly good year for conker production, certainly compared to last year's dearth. They are called "conkers" because of the boyhood game of smashing one conker against another to find the conqueror – the winner.

Apparently, before the invention of X-Boxes and Playstations, when it was not the season for conkers from the trees, boys played conkers with snail-shells so they had year-round conquering entertainment.

The name of the horse chestnut tree is harder to explain. Some sources are silly, saying it comes from an old wives' tale about it producing a nut that cured horses of chest complaints (it is, in fact, not very good for horses to eat conkers).

The best explanation is that when the tree was introduced to this country in the 16th Century, it was thought to be closely related to the sweet chestnut tree, which gets its name from Castanea, in eastern Asia, from where it is said to originate – castanets are so called as they were made from the wood from the tree from Castanea.

But old chestnuts have nothing to do with trees. This phrase can be traced back to a melodrama, The Broken Sword by a Bristol playwrite, William Dimond, which was first performed in London in 1816. One of the characters, Captain Zavior, regularly repeats an anecdote but each time changes an element of it.

As Zavior launches into it for the umpteenth time, he changes the setting for it to a cork tree, at which point his exasperated colleague, Pablo, explodes: "I swear, a chestnut, Captain. This is the 27th time I have heard you relate this story, and you invariably said a chestnut till now."

In the 1880s, this scene became a successful part of the act of American comedian William Warren who would dismiss the punchlines of other actors' jokes by shouting his own at them: "It's an old chestnut."

Such are the mellow fruits of misty autumn.