Q: “Formidable” used to be pronounced FOR-midable in the US, but I believe the

pronunciation was influenced after WWII by British speakers, who pronounced it for-MID-able. For some reason this latter pronunciation has taken hold in the US.

A: Let’s establish at the outset that in modern American usage “formidable” can be pronounced correctly with the accent on either the first or the second syllable (FOR-mid-able or for-MID-able).

Both Merriam-Webster’s Collegiate Dictionary (11th ed.) and The American Heritage Dictionary of the English Language (5th ed.), among others, give the two pronunciations, in that order, as standard English.

We can’t find any evidence, though, that Americans acquired the for-MID-able pronunciation from the British, as you suggest. But the pronunciation does appear to be relatively new—both in the US and in Britain.

For one thing, older standard dictionaries in both countries—even those as recent as the mid-1980s—list only one pronunciation, FOR-mid-able.

And for another, usage guides didn’t begin noticing the word until the mid- to late-20th century, which suggests that its pronunciation wasn’t an issue before then.

Even now, the only pronunciation given in the Oxford English Dictionary is accented on the first syllable (FOR-mid-able). One would think that if for-MID-able were a well-established British pronunciation, and if in fact Americans had acquired it from the British, the OED would list it as a variant.

Yet another British reference book, the latest version of Fowler’s Modern English Usage (revised 3rd ed., 2004), has this to say:

“The standard pronunciation is with the main stress on the first syllable. Second-syllable stressing, though increasingly heard (a limited opinion poll by J. C. Wells, 1990, actually revealed a slight preference for for-MID-able), is not recommended.”

Later the editor of the new Fowler’s, R.W. Burchfield, includes “formidable” in a list of multi-syllable words with “unstable accents.”

Words in which the accent is moving from the first to the second syllable in British usage, he says, include “applicable,” “clematis,” “controversy,” “despicable,” “exquisite,” “formidable,” “harass,” “hospitable,” “integral,” “lamentable,” and others. (Obviously, some of these newer pronunciations have already established themselves in American usage.)

As far as we can tell, the for-MID-able pronunciation seems to be a mid-20th-century phenomenon. The first edition of Fowler’s (1926) doesn’t mention it, nor does our 1956 copy of Webster’s New International Dictionary (the unabridged second edition). But it does show up, among similar “unorthodox” pronunciations, in the second edition of Fowler’s (1965).

Despite that “unorthodox” label in the ’60s, several recent dictionaries, British as well as American, list both pronunciations as standard today. Macmillan, for example, publishes British and American editions, and both of them give the two pronunciations. When both are given, the one accented on the first syllable is invariably listed ahead of the other.

Clearly, however, this pronunciation is in flux. Cambridge Dictionaries Online gives for-MID-able as the standard British pronunciation and FOR-mid-able as the American.

As for why the for-MID-able pronunciation has taken hold, the original Fowler’s offers a clue. In a section about the “recessive accent,” Henry Fowler commented on “a repugnance to strings of obscure syllables.”

Some people’s tongues, Fowler explained, “cannot frame a rapid succession of light syllables hardly differing from each another.” In reaction, he said, they tend either to shift the stress to the second syllable or to drop a syllable.

Fowler used the example of “laboratory,” a five-syllable word (at least it was in his day). Its “orthodox” pronunciation, he said, is accented on the first syllable, but some people “find four successive unaccented syllables trying.”

So rather than accent the first syllable, he said, they accent the second (la-BOR-a-tor-ee) or drop the fourth (LAB-or-a-tree). And, as we know, some British speakers do both (la-BOR-a-tree).

Americans have no trouble accenting the first syllable, but they drop the second (LAB-ra-tor-ee), the usual pronunciation in the US. Fortunately, “lab” is standard English on both sides of the Atlantic.

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