Time for an update on my recent writing for Macmillan Dictionary Blog, where I have three new articles to report.
Colliding with common sense and usage looks at a language peeve over the word collide (and collision, etc.), which says you can use these words:
only when both items in a collision are moving. So if you cycle into a stationary gate, that’s not a collision, but if the gate is swinging at the time, it is a collision. Maybe you find this logical somehow – or maybe, like me, you think it’s awkward and silly. Or it would be, if it were an actual rule.
In the article, I summarise the history of this belief, how it was spread by Bill Bryson and Theodore Bernstein, among others, and what usage experts say about it.
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Fossil words of yore in the offing is a brief survey and description of lexical fossils. If the term is new to you, let me explain:
we may wait with bated breath for something in the offing, but it’s unlikely that anything else in our experience is ever bated, or that we’ve made any other use of the noun offing. (Unless we’re sailors; offing can mean the part of the deep sea visible from the shore.)
These words are known as fossil words, because although they are no longer productive in the language – their creative capacity is not in fine fettle – they have been preserved in set phrases, idioms and contexts. Like physical fossils, they offer a glimpse of earlier times, throwing a light on language from days of yore.
As I go on to show, it’s not just words and short phrases that get fossilised: entire sentences do too, for example if they’re tied to some popular ritual or tradition.
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Finally, The minutiae of Latin plurals addresses the consistently curious nature of English’s curiously inconsistent plurals, specifically Latin imports. I begin with a comparison of personas and personae, and note that:
The two spellings’ coexistence – some call it competition – is not unusual: witness appendixes and appendices, formulas and formulae, millenniums and millennia, referendums and referenda, stadiums and stadia, and thesauruses and thesauri, all used regularly. Neither one in any pair has ousted the other, though some eventually will. Millennia overtook its rival in the 1930s and is likely to maintain its supremacy.
There are no hard and fast rules about which plural to use and when. In certain cases the Latin is more formal or even affected, but not predictably so. Occasionally the two spellings differentiate in meaning.
See if you can think of examples of this last phenomenon, where the Latin plural and the anglicised plural of the same word have diverged semantically. Then read the rest for data on Latin plurals becoming English singulars, and other such fun.
Sentence first 
No doubt what defenders of the “collision” confusion would say is that in order to truly “strike together”, both objects must be active participants in the striking, and in order to do that, they must both approach the intermediate location where the collision takes place.
But they would still be wrong.
‘Referenda’ assumes a Latin singular noun ‘referendum’, with ‘referenda’ as its plural, which, as far as I’m aware, has never existed. ‘Referendum’ is from ‘ad referendum’, in which ‘referendum’ is the accusative neuter singular of the gerundive (an adjective) of the verb ‘refero’, meaning, among many things, ‘consult, refer’, and the construction expresses purpose.’ Referenda’ is thus a false plural.
Adrian: The reasoning seems to go something like that, but I don’t accept it either; to me it seems like an arbitrary regulation insisted upon purely for the purposes of pedantry. If the distinction ever had an etymological justification, that has long since faded.
Barrie: I defer to your knowledge here. My (pocket) Latin dictionary was no help, and none of the usage books I checked had much detail beyond confirming that both referendums and referenda were common plurals in English.