SDG here. (I see there’s been some discussion about differentiating my posts from Jimmy’s; I thought of this yesterday and decided to begin my posts identifying myself.)
In my first post below I mentioned that I don’t share Jimmy’s active interest in language, but here’s a post about the one language I really do have a passion for: English.
I remember as a boy hearing the expression “K.O.” (or “kayo”) for the first time and not knowing what it meant. My mother had said something about plans being “kayoed” by some circumstance, and when I asked her about it she could tell me what the term meant but not what it stood for, what the origin was.
Turning the expression over in my mind a few times, I came to a crashingly obvious hypothesis: “Maybe it’s ‘O.K.’ backwards,” I suggested.
Startled by this insight, my mother felt sure that I was right — until my father appeared and we put the matter to him, and were informed that “K.O.” stands for “knock-out,” as in boxing. My mother was a bit disappointed that my plausible guess had been wrong, but I wasn’t finished yet: Perhaps “okay” was “K.O.” backwards? However, both my parents immediately intuited that this couldn’t possibly be right, even though neither was sure what “O.K.” did stand for.
As it turns out, though, no one else is really totally sure what “O.K.” stands for either. Many dictionaries give “Oll Korrect,” a Germanic expression associated with President Andrew Johnson, as the etymology, but this derivation is uncertain. Other possible eytmologies include “Old Kinderhook” (a nickname of President Martin van Buren), “Aux quais” (a mark on bales of cotton in Mississippi river ports), and “0 Killed” (a negative nightly death toll report in WWI).
There are also many other common expressions in English the actual origins of which are as murky as “okay,” but that have very plausible explanations — as plausible my idea about “kayo” seemed to my mother and me — that are widely believed by many people, but are either actually wrong or else at least only possible, not certain.
For example, many people are certain they know the origin of the phrase “the whole nine yards.” It refers to nine cubic yards of concrete carried by concrete trucks. Or it refers to nine square yards of material used to make a high-quality suit (thus also the phrase “dressed to the nines”). Or it is related to some aspect of WW2 aircraft, or to sailing-ship yardarms rather than yards.
The fact is, no one knows exactly where “the whole nine yards” comes from. Other familiar phrases with similarly uncertain origins include “the real McCoy,” “posh,” and “scot free.”
To read about various proposed or popular explanations for these terms — as well as accepted derivations of phrases such as “high on the hog,” “ringing the changes,” and “willy-nilly” — visit this website!
I’d heard that O.K. started as a joke against bad typists. The typists would say that what ever they typed was “Oll Korrect”, playing off of spelling errors. I had to look this story up online, and found one explanation. Basically, it arose from intentionally misspelling phrases and referring to the misspellings by the abbreviation. “All correct” becomes “Oll Korrect” which becomes “O.K.”
Origin of “the real McCoy”
Elijah McCoy was an African-American inventor who successfully designed an automatic oil cup that may have inspired the popular phrase, “the real McCoy.”
Before this invention, every few miles, the train stopped and the oilman walked the length of the train oiling axles, bearings, and other moving parts. Elijah McCoy invented an oil cup that automatically dripped oil where it was needed.
Even though some tried to imitate McCoy’s cup, the imitations didn’t work as well. The engineers could tell the difference.
Source: http://ecedweb.unomaha.edu/lessons/realmccoy.htm