The first known use of this name was by or before a Congressional committee early in 1860, when the proposal to create a new territory of the Pikes Peak region was before the Congress. In the April 18, 1860 issue of the Rocky Mountain News, Mr. S.W. Beall wrote back to Denver and stated that this name Idaho seemed the most popular suggestion before the committee. On May 10 and 11, 1860, the Congressional Globe mentions the proposals for the Territory of Idaho, and noted that Idaho was an Indian name signifying "Gem of the Mountain." When the territory with Denver as its center was later created, the name Colorado was substituted at the last moment for Idaho. How this name came before the Congress very early in 1860 is unknown. If this was an Indian name known to the miners who flocked to the gold fields in 1859, no mention of the fact was ever made in the newspapers of those days. So perhaps the name was invented by one Dr. George M. Willing; at any rate he claimed to have done so. Willing came to Denver in 1859 from St. Louis and became a candidate for election as delegate to the Congress, despite the lack of any right of the gold miners to have a delegate in Washington. Even though Willing lost the election, he went on to Washington and posed as the properly elected delegate. He claimed that he there invented the name Idaho, it being suggested by the presence of a little girl, Ida. His relation of the matter was published by a friend of his, William O. Stoddard, in the New York Daily Tribune for December 11, 1875...

The Territory of Colorado was actually created February 28, 1861. That was the end of the official interest in the word for the Pikes Peak area. It was after these "Colorado" events that we find the word being used in what became the state of Idaho. In December, 1861, the territorial legislature of Washington created an Idaho County, and it later became a county of the state of Idaho. Joaquin Miller, the "poet of the Sierras," was responsible for several versions of how the word Idaho was first put into that form by him in the winter of 1861-1862. In one of these accounts Miller spells the name "E-dah-hoe" and says that it was an Indian word meaning "the light or diadem on the line of the mountain." A number of historians of the state of Idaho have accepted this story from Miller, but others have noted that the name was well known and used before Miller appeared upon the scene. The Territory of Idaho was created on March 3, 1863, again after the Congress nearly adopted another name, Montana.

I read that "kangaroo" was Aborigini for "I don't understand". So when people asked (in English) what the animal was, the natives replied "Kangaroo" and the name stuck. I have also read , however, that this may not be a true story.

I thought that we've established that idaho doesn't exist! It doesn't!

'Round Idaho way, lots of people say that the original (native) name of the place was "Idanha." I don't remember what that name was supposed to mean, and I'm not sure where the story comes from, but I've heard it several times. I even knew some people who started a company called "Idanha Films," in honor of their native state.

The "Kangaroo = I don't understand" story has been convincingly debunked.
It turns out "Kangaroo," or a similar word, was indeed the name of the jumping marsupial we all know and love in one of the native languages of coastal Australia, so Captain Cook and his men surely heard the local people using this word for the animal in question.
Remember that there are hundreds of different aboriginal languages in Australia, so a perfectly good word in one village could be pure gibberish to people a few miles away.

I've always liked the story about how Truth or Consequences, New Mexico, got its name. There was a very popular radio (and later TV) quiz show by that name, and the people in one New Mexico village thought they could get the show to relocate there if they changed their town name to Truth or Consequences. The show declined to move there, though, since rural New Mexico was inconveniently far from any communications centers. Despite this, the name stuck.

So it's probably only a matter of time until we have a Weakest Link, Maryland, a Fear Factor, Arakansas, and a Survivor, New York.

There is a Dish, Tx, right? ;o)

I've heard that a lot of different words mean "I don't know" or "I don't understand" in the "native" language. Most stories just seem to piggy back off a more original story.

I can't find Dish, Texas in my atlas, but there are plenty of fun names in Texas.
Texas is a very large state with a big population, so it has thousands of town names and other place names, and naturally some of them are strange or amusing.

Some of my favorites are:

Gun Barrel City
Turkey
Old Dime Box (which, of course, is near Dime Box)
Muleshoe
Argyle (a good place to buy socks?)
Cut and Shoot
Isleta (which means "little island" and is in the middle of the desert)
Matagorda (which means "kill a fat lady")

I also like the name "Falfurrias," which means nothing that I know of, but I like the way it sounds.

"Texas," by the way, comes from a Caddoan word meaning "friend" or "ally." Apparently the Caddo people shouted this to the Spanish conquistadores who were about to shoot them. The Spanish took it to be the name of the tribe, and named the whole state after them.

> I thought that we've established that idaho
> doesn't exist! It doesn't!
Reminds me of something out of a Garfield cartoon in which he claims Wyoming doesn't exist.

The Native American languages experts disagree. It was a fairly common word coming from the Kiowa-Apache language idahee "enemy" applied to the Commanches when they migrated into southern Colorado. It was used in the names of several towns from Colorado to Ohio.

The best explanation of the origin of 'Idaho' may be found here http://www.alphadictionary.com/articles/state_name_origin.html#idaho

Here is an explanation based on solid research:
http://www.alphadictionary.com/articles/state_name_origin.html

Sorry. I wrote my comment before reading all of those already here.