That’s how we should be pronouncing apostrophe, according to the OED: “It ought to be of three syllables in Eng. as in French, but has been ignorantly confused with the prec. word”—the prec. word being apostrophe ‘A figure of speech, by which a speaker or writer suddenly stops in his discourse, and turns to address pointedly some person or thing, either present or absent; an exclamatory address.’ The name of the punctuation mark, you see, is not from Greek/Latin apostrophê (which would justify the extra syllable) but (via French apostrophe—three syllables!) from Latin apostrophus, itself from Greek (hê) apóstrophos (sc. prosôdia the accent) ‘of turning away, or elision.’ So there’s no earthly reason to say “apostro-fee,” and yet we do anyway, perverse creatures that we are. Why don’t all the preservers of the purity of English take up this cause, now that they realize the error of everyone’s ways? I’d like to hear William F. Buckley lean back in his inimitable way and denounce “the illiterate use of apostroffs in plurals.”
But of course that’s a fantasy; the preservers ignore the ahistorical pronunciation and focus on that damnable plural use. In fact, according to the latest lament for the apostrophe, a Telegraph article by Matt Born, the “‘greengrocer’s apostrophe’—so-called because of shopkeepers’ propensity to display signs for ‘pear’s’ or ‘banana’s'” is the object of ever-increasing angst; it’s spreading so fast that “it threatens to undermine what has long been a strict rule of grammar.” Worst of all, “over time it may become acceptable.” I leave to the imagination the horrors that such an outcome would unleash upon an already suffering world.
But wait: what does the OED say in small type, there at the end of definition 2 (“The sign (‘) used to indicate the omission of a letter or letters… and as a sign of the modern English genitive or possessive case”)? It says… it says…
In the latter case, it originally marked merely the omission of e in writing, as in fox’s, James’s, and was equally common in the nominative plural, esp. of proper names and foreign words (as folio’s = folioes); it was gradually disused in the latter, and extended to all possessives, even where e had not been previously written, as in man’s, children’s, conscience’ sake. [Emphasis added.]
Why, that means that the apostrophe was originally, and thus properly, used in the plural; those greengrocers are right, and the Apostrophe Protection Society is wrong! Surely the Williams (Buckley and Safire) and the other preservers will lay off the ancient plural apostrophe and begin working on excising that excrescent final syllable. (OED citations and links to article and Society courtesy of The Discouraging Word, which should not be held responsible for the puckishly antinomian stance taken by this website.)