"The name turkey was originally applied to an African bird (now known as the guinea fowl) which was believed to have come from Turkey. When the Europeans stumbled on the American turkey, they thought it was the same bird--so they named it 'turkey.'"

source: http://www.fsis.usda.gov/oa/educator/educa2-4.htm

I don't know how accurate this is but considering that they called the natives "Indians" it doesn't seem too unlikely for them to name the bird "turkey!" Obviously their vocabulary was pretty limited!!!

When Europeans first encountered these species in the Americas, they incorrectly identified them with the African Helmeted Guineafowl (Numida meleagris), also known as the turkey-cock from its importation to Europe through Turkey, and the name of that country stuck as also the name of the American bird. The confusion is also reflected in the scientific name: meleagris is Greek for guinea-fowl.
Wild Turkeys may occasionally be found in urban areas.
Enlarge
Wild Turkeys may occasionally be found in urban areas.

The names for the Turkey in other languages also frequently reflect its exotic origins, seen from an Old World viewpoint, and confusion about where it actually comes from.

Wow, thanks to all the learned input on the subject. I think I can accept the "Turkey-cock" as the explanation for it, and the point about exotic naming was also interesting, since it obviously applies to the Persian name as well, in this case, MEANING exotic!

I am just a bit skeptical on the point of "Turkey-cock" since the name in this format was not applied to the country in the 17th century, obviously. It was then the Ottoman Empire. I would imagine even if they were trying to connect the bird to the country, they would have used the relative noun, calling it "Turkish", not Turkey. I am a bit unsure of this etymology which sounds a bit too "folky" for my taste.

سلام.احتملا آنها نيز بر لا يفهمات لقب تركي نهاندي و قومي را به خشم آوردي!!

Actually, Europeans identified Ottoman empire as "Turkey". You may want to refer to any archive of old maps. An example: the commander of Vienna during the second siege by Ottomans was called "Turken Louis" (Luois the Turk if you will, since he had spent a long time in the Ottoman empire and spoke Turkish fluently), but not Ottoman Louis.

در مورد اون سئوال آخری: به نظر میاد بوقلمون از ترکیه وارد انگلیس شده بوده و به نام "خروس ترکی" و بعدها "ترکی" معروف بوده.
http://family.silvert.org/vicki/recipes/turkey.htm

ٍSee, that's the issue exactly. I didn't claim that the designation Turk, as an ethnic and national name was not used, and your exaple, as you know, shows that he was the "Turkish" Louis, but not Louis from "Turkey", as the name of a nation of geographical area.

It goes back to the issue of nations and nation-states. For example, "France" was not called France up to the 17th century, rather The Land of the French (Frankia) and the king of France was properly "the king of the French". Even Napoleon calls himself "The Emperor of the French" not "of France".

So, there is no argument that the designation "Turk" and "Turkish" were used to refer to various things coming from the Ottoman territories, but was the name Turkey really ever applied to the country as a geographical entity prior to the 20th century?

I once read something in New York Review of Books by Bernard Lewis about this (the words "turkey", "orange", etc.) but I don't quite recall his fatwa about the status of the word turkey. (About "orange" he had mentioned, if I'm not mistaken, that the word is originally Persian, but Iranians call it "porteghaal".)

I found the article for you.

Orange is indeed from a "Persian" root, it is from "Torang" (Toranj) which originally in Persian had the meaning of a citrus that was sour (like Naarenj). The word was taken to Europe by the Arabs.

The reason we call orange "Porteghal" is that the Portuguese brought Sweet Oranges to the Middle East.