As an adjective, "okay" means "adequate," "acceptable" ("this is okay to send out"), "mediocre" often in contrast to "good" ("the food was okay"); it also functions as an adverb in this sense. As an interjection, it can denote compliance ("Okay, I will do that"), or agreement ("Okay, that's good"). As a verb and noun it means "assent" ("The boss okayed the purchase," and, "The boss gave his okay to the purchase.") A versatile discourse marker (or back-channeling item), it can also be used with appropriate voice tone to show doubt or to seek confirmation ("Okay?" or "Is that okay?").
Proposed etymologies 
There is no consensus on the origins of "okay." Several possibilities exist.
The folk singer Pete Seeger sang that "okay" was of Choctaw Indian origin, as the dictionaries of the time tended to agree. Three major American reference works (Webster's, New Century, Funk & Wagnalls) cited the Choctaw etymology as the probable origin until as late as 1961.
The earliest evidence for this is provided in work by the missionaries Cyrus Byington and Alfred Wright in 1825. These missionaries ended many lines in their translation of the Bible with the particle "okeh" (often sentence final) meaning "it is so".
Subsequent Choctaw spelling books de-emphasized the spellings lists in favor of straight prose, and they made use of the particle[,] but they too never included it in the word lists or discussed it directly. The presumption was that the use of particle "oke" or "hoke" was so common and self-evident as to preclude any need for explanation or discussion for either its Choctaw or non-Choctaw readership.—
A brief search through Byington's Dictionary of the Choctaw Language confirms the ubiquity of the "okeh" particle.
The Choctaw language was spoken at this time in the South-Eastern United States. The major language of trade in this area, Mobilian Jargon, was based on Choctaw-Chickasaw, two Muskogean-family languages. This language was used, in particular, for communication with the Cherokee (an Iroquoian-family language).
West African 
A verifiable written attestation of the particle 'kay' is from a North Carolina slave not wanting to be flogged by a European visiting America in 1784:
Kay, massa, you just leave me, me sit here, great fish jump up into da canoe, here he be, massa, fine fish, massa; me den very grad; den me sit very still, until another great fish jump into de canoe;...—
David Dalby first made the claim that the particle "okay" could have African origins in the 1969 Hans Wolff Memorial Lecture. His argument was reprinted in various newspaper articles between 1969 and 1971. This suggestion has also been mentioned more recently by Joseph Holloway, who argued in the 1993 book The African Heritage of American English (co-written with a retired missionary) that various West African languages have near-homophone discourse markers with meanings such as "yes indeed" or which serve as part of the back-channeling repertoire. Though Frederic Cassidy challenged Dalby's claims, asserting that there is no documentary evidence that any of these African-language words had any causal link with its use in the American press, one can certainly wonder at the fact that this standard of written proof does not account for the illiteracy in which the West African speakers were kept during the period of slavery in question.
In present-day American English, both "kay" and "m'kay" are attested modern pronunciations of the term. The fact that the onset /mk/ is foreign to English phonotactics may lend some support to the idea advanced by Dalby that "okay", along with "uh-huh" (yes) and "huh-uh" (no) -- and presumably the corresponding intonation patterns on "mm-hm", "mm-um"—have a West African origin.
Boston abbreviation fad 
The etymology that most reference works provide today is based on a survey of the word's early history in print: a series of six articles by Allen Walker Read in the journal American Speech in 1963 and 1964. He tracked the spread and evolution of the word in American newspapers and other written documents, and later throughout the rest of the world. He also documented controversy surrounding okay and the history of its folk etymologies, both of which are intertwined with the history of the word itself. Read's work has nevertheless been called in for closer scrutiny by scholars of both Choctaw and West African languages.
In it he argues that, at the time of its first appearance in print, a broader fad existed in the United States of "comical misspellings" and of forming and employing acronyms, themselves based on colloquial speech patterns.
The abbreviation fad began in Boston in the summer of 1838 … OFM, "our first men," and used expressions like NG, "no go," GT, "gone to Texas," and SP, "small potatoes." Many of the abbreviated expressions were exaggerated misspellings, a stock in trade of the humorists of the day. One predecessor of okay was OW, "oll wright."—
The general fad is speculated to have existed in spoken or informal written U.S. English for a decade or more before its appearance in newspapers. OK's original presentation as "all correct" was later varied with spellings such as "Oll Korrect" or even "Ole Kurreck".
The term appears to have achieved national prominence in 1840, when supporters of the American Democratic political party claimed during the 1840 United States presidential election that it stood for "Old Kinderhook," a nickname for a Democratic presidential candidate, Martin Van Buren, a native of Kinderhook, New York, who was Andrew Jackson's protégé. "'Vote for OK' was snappier than using his Dutch name." In response, Whig opponents attributed OK, in the sense of "Oll Korrect," to Andrew Jackson's bad spelling. The country-wide publicity surrounding the election appears to have been a critical event in okay's history, widely and suddenly popularizing it across the United States. Read had originally proposed an etymology of "okay" in "Old Kinderhook" in 1941. The evidence presented in that article was somewhat sparse, and the connection to "Oll Korrect" not properly elucidated. Various challenges to the etymology were present, e.g. Heflin's 1962 article. However, Read's landmark 1963-1964 papers silenced most of the skepticism. Read's etymology gained immediate acceptance, and is now offered without reservation in most dictionaries. An extensive rebuttal of this theory is offered by Jim Fay at the The Illinois Prairie Info website
Alternative etymologies 
A large number of origins have been more or less seriously proposed. Some of them are thought to fall into the category of folk etymology and are proposed based merely on apparent similarity between "okay" and one or another phrase in a foreign language with a similar meaning and sound. Some examples are
- A corruption from the speech of the large number of descendants of Scottish and Ulster Scots (Scots-Irish) immigrants to North America, of the common Scots phrase "och aye" ("oh yes").
- Derivation from the Lakota word "Hokaheh" (also anglicised as "Hoka Hey" and "Hoka Hay") which has many popular mistranslations but which is probably most accurately rendered as "Let's go!". (This is additionally unlikely in that contact with the Lakota people was not really established at the time that "okay" or "ok" was first noted.)
- The loan of the Greek phrase Όλα Καλά or Ola Kala, meaning "All Good."
Early history 
The scholarly consensus, based on Allen Walker Read, identifies the earliest known use of O.K. in print as 1839, in the March 23 edition of the Boston Morning Post (an American newspaper). The announcement of a trip by the Anti-Bell-Ringing Society (a "frolicsome group" according to Read) received attention from the Boston papers. Charles Gordon Greene wrote about the event using the line that is widely regarded as the first instance of this strain of okay, complete with gloss:
The above is from the Providence Journal, the editor of which is a little too quick on the trigger, on this occasion. We said not a word about our deputation passing "through the city" of Providence.—We said our brethren were going to New York in the Richmond, and they did go, as per Post of Thursday. The "Chairman of the Committee on Charity Lecture Bells," is one of the deputation, and perhaps if he should return to Boston, via Providence, he of the Journal, and his train-band, would have his "contribution box," et ceteras, o.k.—all correct—and cause the corks to fly, like sparks, upward.
Read gives a number of subsequent appearances in print. Seven instances were accompanied with glosses that were variations on "all correct" such as "oll korrect" or "ole kurreck," but five appeared with no accompanying explanation, suggesting that the word was expected to be well known to readers and possibly in common colloquial use at the time.
Formerly, various claims of earlier usage had been made. For example, it was claimed that the phrase appeared in a 1790 court record from Sumner County, Tennessee, discovered in 1859 by a Tennessee historian named Albigence Waldo Putnam, in which Andrew Jackson apparently said "proved a bill of sale from Hugh McGary to Gasper Mansker, for an uncalled good, which was O.K.". However, Read challenged such claims, and his assertions have been generally accepted.
David Dalby (see above) brought up some other earlier attested usages. One example from 1941 is the apparent notation "we arrived ok" in the hand-written diary of William Richardson going from Boston to New Orleans in 1815, about a month after the Battle of New Orleans. Frederic Cassidy asserts that he personally tracked down this diary and notes that:
After many attempts to track down this diary, Read and I at last discovered that it is owned by the grandson of the original writer, Professor L. Richardson, Jr., of the Department of Classical Studies at Duke University. Through his courtesy we were able to examine this manuscript carefully, to make greatly enlarged photographs of it, and to become convinced (as is Richardson) that, whatever the marks in the manuscript are, they are not OK.—
Similarly, H. L. Mencken, who originally considered it "very clear that 'o. k.' is actually in the manuscript", later recanted his endorsement of the expression, asserting that it was used no earlier than 1839. Mencken (following Read) described the diary entry as a misreading of the author's self-correction, and stated it was in reality the first two letters of the words a h[andsome] before noticing the phrase had been used in the previous line and changing his mind.
Another example given by Dalby is a Jamaican planter's diary of 1816, which records a black slave saying "Oh ki, massa, doctor no need be fright, we no want to hurt him". Cassidy asserts that this is a misreading of the source, which actually begins "Oh, ki, massa ...", where ki is a phrase by itself:
In all other examples of this interjection that I have found, it is simply ki (once spelled kie). As here, it expresses surprise, amusement, satisfaction, mild expostulation, and the like. It has nothing like the meaning of the adjective OK, which in the earliest recorded examples means 'all right, good,' though it later acquires other meanings, but even when used as an interjection does not express surprise, expostulation, or anything similar.—
Spelling variations 
Whether this word is printed as OK, okay, or O.K. is a matter normally resolved in the style manual for the publication involved. Dictionaries and style guides such as the Chicago Manual of Style and The New York Times Manual of Style and Usage provide no consensus.
|okeh||An alternative English spelling, no longer common. Also see Okeh Records.|
|kay or 'kay||Notably used in Herman Wouk's The Caine Mutiny as a filler word by the maniacal Captain Queeg.|
|k or kk||Commonly used in instant messaging, or in SMS messages. Before the days of SMS, "K" was used as a Morse code prosign for "okay."|
|Okie dokie||This slang term was popularized in the film "The Little Rascals" (Oki doki). The phrase can be extended further, e.g. "Okie dokie (ala) pokie / smokie / artichokie / karaoke / lokie," etc.|
|okej||Used in Poland, although ok is more common in written language; sometimes oki is said.|
|ôkê||Used in Vietnam; okey also used, but ok more commonly.|
|okei||Used in Norwegian, Finnish and Estonian (together with OK or ok)|
|okey||Used in Castellano (Spanish) and Turkish, sounding similar to the English pronunciation OK.|
|okace||Used mainly in text/internet messaging by people from Catalonia.|
|okej||Used in Swedish, Slovene, Serbian, Polish, Croatian, Bulgarian, Macedonian and sometimes Latvian; ok also used, but less common.|
|oké||Used in French, Dutch and Hungarian. In Dutch, okee, ok and okay are also used, but are less common in the formal written language.|
|ookoo||Used in Finland. Pronounced the same way as "OK," but spelled like the pronunciation of the letters.|
|oukej||Used in Czech and Slovak. Pronounced as the English OK. When written OK, it is pronounced [o:ka:]. Neither version recognized as official.|
|O.K||Used in Greek. The abbreviation is pronounced as the English OK.|
|oukei||Used in colloquial Afrikaans. Pronounced also as "OK".|
|M'kay||Slang term popularized by South Park TV show. Pronounced also as "Mmmm K".|
|Ócápa||Used in colloquial Portuguese. Pronounced also as "OK".|
Okay can mean "all right" or "satisfactory." For example, "I hope the children are okay" means "I hope the children are all right"; "I think I did OK in the exam" means "I think I did well, but not perfect, on the exam"; and "he is okay" means "he is good," or "he is well," depending on context.
Okay meaning "all right" can be used as the stand-alone question Okay? asking if there are any problems or confusion. This question can also be used as an informal greeting, as in "Okay, Jack?" equivalent to "How are you, Jack?"
Depending on context and inflection, okay can also imply mediocrity. For example: "The concert was just okay."
Okay can be used as an adjective or adverb: "He ran an OK race," "He did OK."
Okay can be used as an affirmative answer to a question or to express agreement with a statement, similar in both cases to "Yes."
Saying okay in a sarcastic or questioning tone or elongating the word can indicate that the person one is talking to is considered crazy and/or exasperatingly stubborn in their view. "I really saw a UFO last night!" "Okay..."
Okay! can also be used as an exclamation in place of words like "enough!" or "stop!"
Okay can be a noun or verb meaning approval. "Did you get the supervisor's okay?" "The boss okayed the proposal."
Okay has multiple uses in public speaking. As an interjection at the opening of a speech, lecture, or reading, okay is used to call for the audience's attention and to signal that the speaker is about to begin. Similarly, it can be used as a section break in the middle of speech to mark a shift in topic. Finally, okay can be used at the end of a speech, lecture, or explanation to request listener feedback, similar to "Are you with me?" or "Do you understand?" Based on context and convention, this usage can be seen as asking for various responses ranging from simple, silent headshaking or nodding to full, detailed questions or rebuttals.
When used in phone texting or short message system (SMS), "Okay" is occasionally truncated to a single "k."
International usage 
In Brazil, Mexico and Peru, as well as in other Latin American countries, the word is pronounced just as it is in English and is used very frequently. Although pronouncing it the same, Spanish speakers often spell the word "okey" to conform with the pronunciation rules of the language. In Brazil, it may be also pronounced as "ô-kei." In Portugal, it is used with its Portuguese pronunciation and sounds something like "ókâi" (similar to the English pronunciation but with the "ó" sounding like the "o" in "lost" or "top").
Arabic speakers also use the word (أوكي) widely, particularly in areas of former British presence like Egypt, Jordan, Israel/Palestine and Iraq, but also all over the Arab world due to the prevalence of American cinema and television. It is pronounced just as it is in English but is very rarely seen in Arabic newspapers and formal media.
In Israel, the word okay is common as an equivalent to the Hebrew words בסדר [b'seder] ('in order') and טוב [tov] ('good'). It is written as it sounds in English אוקיי.
It is used in Japan and Korea in a somewhat restricted sense, fairly equivalent to "all right." Okay is often used in colloquial Japanese as a replacement for 大丈夫 (daijōbu "all right") or いい (ii "good") and often followed by です (desu — the copula).
In Chinese, the term "好" (hǎo; literally: "good"), can be modified to fit most of usages of okay. For example, "好了" (hao le) closely resembles the interjection usage of okay. The "了" indicates a change of state, in this case it indicates the achievement of consensus. Likewise, "OK" is commonly transformed into "OK了" (OK le) when communicating with foreigners or with fellow Cantonese speaking people in at least Hong Kong and possibly to an extent, other regions of China. Other usages of Okay such as "I am okay" can be translated as "我还好." In Hong Kong, movies or dramas set in modern times use the term "ok" as part of the sprinkling of English included in otherwise Cantonese dialog. In Mandarin, it is also, somewhat humorously, used in the "spelling" of the word for karaoke, "卡拉OK," pronounced "kah-lah-oh-kei" (Mandarin does not natively have a syllable with the pronunciation "kei"). On the computer, okay is usually translated as "确定," which means "confirm" or "confirmed."
In Taiwan, OK is frequently used in various sentences, popular among but not limited to younger generations. This includes the aforementioned "OK了" (Okay le), "OK嗎" (Okay ma), meaning "Is it okay?" or "OK啦" (Okay la), a strong, persuading affirmative, as well as the somewhat tongue-in-cheek explicit yes/no construction "O不OK?" (O bu Okay), "Is it okay or not?."
In France, OK is used to communicate agreement, and is generally followed by a French phrase (e.g. OK, d'accord).
In the Philippines "okay lang" is a common expression, literally meaning "just okay" or "just fine." They also use it in sms but with the letter "k" only which means okay also. Sometimes spelled as okey.
In Malay, it is frequently used with the emphatic suffix "lah": OK-lah.
In Vietnamese, it is spelled "Ô kê".
In India it is often used after a sentence to mean "did you get it?", often not regarded politely, for example, "I want this job done, okay?" or at the end of a conversation (mostly on the phone) followed by "bye" as in, "Okay, bye."
In Germany, OK is spelled and pronounced as in English. The meaning ranges from acknowledgement to describing something neither good nor bad, same as in US/UK usage.
In Maldivian Okay is used in different ways, often used to agree with something, more often used while departing from a gathering "Okay Dahnee/Kendee."
In Japan, it is spelled Okkei and pronounced as in English with minor stress on OK as in OAK then Kei.
In the United States and much of Europe a related gesture is made by touching the index finger with the thumb (forming a rough circle) and raising of the remaining fingers. It is not known whether the gesture is derived from the expression, or if the gesture appeared first. The gesture was popularized in America in 1836 as a symbol to support then Presidential candidate Martin Van Buren. This was because Van Buren's nickname, Old Kinderhook, derived from his hometown of Kinderhook, NY, had the initials O K. Similar gestures have different meanings in other cultures.
OK is used to label buttons in modal dialog boxes such as error messages or print dialogs, indicating that the user must press the button to accept the contents of the dialog box and continue. When a modal dialog box contains only one button, it is almost always labeled "OK" by convention and default, usually rendered to the screen in upper case without punctuation: OK, rather than O.K., Okay, or Ok. The OK button can probably be traced to user interface research done for the Apple Lisa.
The Forth programming language prints ok when ready to accept input from the keyboard. This prompt is used on Sun, Apple, and other computers with the Forth-based Open Firmware (OpenBoot). The appearance of ok in inappropriate contexts is the subject of some humor.
In HTTP, the HyperText Transfer Protocol, upon which the World Wide Web is based, a successful response from the server is defined as OK (with the numerical code 200 as specified in RFC 2616). The Session Initiation Protocol also defines a response, 200 OK, which conveys success for most requests (RFC 3261).
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Further reading 
- Metcalf, Allan. (2011). OK: The Improbable Story of America's Greatest Word. Oxford University Press, Oxford. ISBN 978-0-19-537793-4
|Look up okay in Wiktionary, the free dictionary.|
- Where did OKAY come from?
- The Choctaw Expression Okeh and the Americanism Okay
- Ok. Let's continue.
- Most Recognized Word on the Planet: OK or O.K. or Okay
- Origin of the Word OK
- NPR: The Origin of OK (audio)
- OK/OKAY- Exhibition at the Grey Art Gallery, Swiss Institute, New York University
- FAQ: "OK"
- BBC: How 'OK' took over the world. Retrieved 18 February 2011.