How did the word buoy come to be pronounced "BOO-ee" in most of the US? The British pronunciation "BOY" as in the word buoyancy or buoyant (which both countries pronounce the same) seems to be pretty straight-forward, so where did the US version come from?
buoy (n.) late 13c., perhaps from either O.Fr. buie or M.Du. boeye, both from W.Gmc. **baukn* "beacon" (cf. O.H.G. bouhhan, O.Fris. baken). OED, however, supports M.Du. boeie, or O.Fr. boie "fetter, chain" (see boy), "because of its being fettered to a spot."
So you have two possible origins, one originally pronounced [bɥi(ə)] (French) or [bœɛi] (Dutch), and the other [boi] (French) or [bœi] (Dutch), all of which could be Anglicised as either disyllabic [buwiː] (boo-ee) or monosyllabic [bɔɪ] (boy).
I suspect both pronunciations have been around for a while in English, and the colonial divide just drew a more distinct (regional) line between them.
One common 18th century pronunciation of buoy in England (and presumably also America), seems to have been bwoy (/bwɔɪ/). The book A Practical Grammar of English Pronunciation by Benjamin Humphrey Smart (London, 1810) says
Bw, in the words
(9) Buoy, buoyance
is represented by bu. They should never be pronounced boy, boyance.
I believe that this comment shows that both bwoy and boy were used in 1810 England. This pronunciation also explains why buoy is not spelled boy.
The 1892 Webster's High School Dictionary gives both boy and bwoy as pronunciations.
It's not hard to imagine the pronunciation bwoy turning into boo-ee. But it's also possible that in 18th century England, besides the pronunciations boy and bwoy, there was a third, boo-ee, which now only survives in the U.S. I would tend to lean towards the theory that the boo-ee pronunciation was brought to American from England, because the OED gives a 1603 citation where the word is spelled "bowie", which seems to indicate that this pronunciation existed in England then.
Finally, addressing the question of which pronunciation of buoy is "correct"—according to Mr. Smart, we're all pronouncing it wrong.
Having grown up in Maryland and Virgina, states with as much water as land, and having a long maritime tradition, I have always heard the word as Boo-wee, and it was a shibboleth, to see if you were really a boater/yachter, as mountain folk (from western MD, western VA and WV) were consistantly ignorant of yachting terms and always struggled to pronounce it correctly. I had never heard 'boy' until travelling to New England. Boatswain, pronounced Bow-sun, and the bow of a ship, pronounced bau, not bo, were similarly used as shibboleths. During the 1960s and 70s, there was a consistant tension between WASPs and Ethnics, and mountain folk, although as Anglo-Saxon as one cared to be, were still treated like they had "foreign" blood by the WASP elites. As an Irish Catholic with a grandmother in West Virginia, I was one of these people whose family had come in from elsewhere, and by sending me to prep school in Annapolis Maryland and by owning a boat, my parents made it possible for me to pass as "lily" white, as long as they didn't hear my last name, which was conveniently missing it's O'.
Now as for why we use this pronunciation, it seems closer to the Dutch words mentioned by others in this forum, and I suspect it is the New York pronunciation, as people still speak with a strong Dutch accent there, saying "Duh" for "Dhuh", as in "Get in the car" (pron. "duh caa"). To outsiders, New Yorkers can be unintelligible, even to other people from relatively nearby places, like upstate NY, Phildelphia, or Connecticut. In general, the DC area has a distinctly Southern accent, and I believe the pronunciation "Boy" is limited to New England, which still has traces of an English accent. As for pronouncing it like it's spelled, "uo" would be "oo", and "y" would be "ee". As usual, the English vowels U and O always have a trailing "W" sound, hense "ee" becomes "wee".
My humble speculation,
Maxx (O') Cassidy, of Bowie (Prounouced Buoy), Maryland, USA.
If I may add my two cents I'd like to suggest the possibility that the two variants may be related to context of usage as opposed to region or current social class. I grew up in Michigan where my grandfather was an antiques dealer. I have never heard of the pronunciation of "boo-ee" until today. All my exposure to the word buoy has been in relation to "buoying up the price/market" in an auction/stock market setting. Having been personally only marginally interested in such activities, I have never been confident in my own pronunciation, at times alternating between "boy" and "bwoy" (i.e. buuuoy), but at no times would I have ever thought to say "boo-ee".
It may be that the mariners on the eastern seaboard of the united states, being descendants of a wide variety of social classes not always related to the former maritime tradition of the british isles began to seek new profesions as a way to support themselves and started the eastern U.S. maritime pronunciation, which was bequeathed to navegators and explorers as they began the westward expansion.
Merchants and stock brokers (especially maybe due to their college training) acquired their vernacular from different sources, and being that the word buoy has never been in common parlance except as a technical term, have never been exposed to the alternate pronunciation. This would possibly explain why boating enthusiasts in present day minnesota use eastern u.s. maritime pronunciation, whereas others in the same state report of having never heard it.
Also possibly of interest is the relation to the word buy, especially in the price fixing definition of buoy. etmonline.com lists the roots of buy as being old english. Buoy, however, is reported as having been of spanish origin, namely "boyar" to float. Is it too far fetched of an idea to postulate that "boyar" itself may have been descended from english buy? (I can find no etymological roots for boyar online in spanish or in english) Both countries have long maritime traditions, and other english commerce words inherited from spanish include account and accountant. I'm sure there are other examples but I can't think of any at the moment. Could this theory, if true, explain how buoy has also come to mean 'buy' full circle?
Pronunciations of buoy are not governed only those who happen to live near a seaboard, let alone which region. I'd grown up in Minnesota, about as far from an ocean as we get in North America, and had always heard and used the word 'buoy' as a homonym of boy, never the two-syllable pronunciation boo-ee.
The first several times I'd heard it as if it were boo-ee, I was startled at itswhat I believed to be mispronunciation. The 'buoy' part of words like buoyant has in my experience always been the 'boy' sound, also as used in the phrase 'buoyed up' meaning that something was lifted or had risen, had become more cheerful, usually due to good news or something of that sort.
It's not merely a mid-western regional pronunciation, either. Lifebuoy is a long-established soap brand of Unilever. Two syllables not three, accent on the first syllable, pronounced life-boy.