Oxbow lakes. Remember them? A curved lake that was once part of a meandering river is an interesting natural feature, I suppose, but you'd need to be a dedicated geographer to get worked up about them, wouldn't you?
Unless you are a regular poster in the TES Opinion and Personal forums.
Over the past year, the two words have become freighted with so much social, political and even emotional significance that it's enough for some hapless ingenue to utter the phrase to trigger yet another bout of hostilities.
Let me explain. Earlier this year, Eureka! cited "oxbow lakes" as an example of the sort of "useless" knowledge traditionalists believe must be hammered into children so they might pass exams and become obedient citizens.
The words soon became a shorthand for the entire conservative educational philosophy, a club with which the progressives could bludgeon the old-school, chalk-and-talk, filling-an-empty-vessel brigade. The trad v prog debate smouldered through the summer and has flared up again recently, fanned by Tomlinson and the two Charleses, Clarke and Prince.
But there's more to these oxbows than politics. For people of a certain age, the phrase has a certain Proustian kick, evoking the whole ghastly - or was it glorious? - world of 1950s60s secondary schools, leather patches, ice-cold showers, textbooks wrapped in brown paper, prefects, the lot.
And so it was in early November that one of our better satirists, daddyorchips, started the "Oxbow lakes mon amour" thread with this fetching verse:
"Sinuous Moist Orphan of the winding river You caress me with your silt A victim of alluvial lust."
Suddenly, closet oxbow lake fanciers were outing themselves all over our Personal forum. When Nomad posted a link to an admittedly astonishing aerial photograph of a series of oxbow lakes in Colorado, daddyorchips could not help himself: "oh, i say !! ): ))".
Some wondered if we might be witnessing the birth of a new psychosexual obsession, but our satirists had already moved on. On Monday, daddyorchips posted a freeform poem in praise of eskers. Esker? That's a long ridge of sand and gravel deposited by a stream, you dolt. And as we now know, thanks to daddyorchips, "salopis chocablocwiththeblighters".
Bill Hicks is editor of the TES website. www.tes.co.ukstaffroom