Purist Alert! Purist Alert!
The original hootenannies, back in the Forties and Fifties, were gatherings of folk singers who got together to swap songs and generally jam. A very few of these were in halls such as the Friends Meeting House or the lounge in Eagleson Hall (the U. of W. student YM/YWCA), but the vast majority of them were in private homes. They were unstructured. There was lots of solo singing, some group songs, some sing-alongs, and often a chance for a beginner to try out his or her stuff in front of other singers and folks who were generally sympathetic, supportive, and helpful. There was no segregation of singers and non-singers—which is to say, it was not a "performer / audience" thing.

The point is, a hootenanny was (and still is, here in Seattle) an informal get-together of, by, and for folk-oriented singers and musicians. If others wanted to come and listen, as long as they weren't just "party-crashers" and behaved themselves, they were welcome:   including welcome to haul off and sing something if they wanted to (you never knew what might pop up!). There was no kind of admission charge. If any money changed hands at all, it was to kick in for the case of beer or the jug of cheap wine (the hoots at the Friends Meeting House and at Eagleson Hall were non-alcoholic, of course, which may account for private homes being the location of choice, although drinking was moderate and I rarely saw anyone get sloshed at a hoot).

As Ron says, Pete Seeger and Woody Guthrie picked up the word in Seattle in the Forties. When they got back to New York, they started calling the Saturday afternoon gatherings at the house they shared with a whole bunch of other singers "hootenannies," and the word spread from there. Pete describes this in his book, The Incompleat Folksinger. The word meant "an informal gathering of folk singers." [Note:   I think Pete said that they did ask something like 35¢ (hat in the middle of the floor), because they were trying to get enough money together to pay the rent. Sort of like British "skiffle parties," to raise rent money.]

When, after the Kingston Trio's recording of "Tom Dooley" hit the charts in 1958 and the Pundits of Profit learned, to their surprise, that there was money to be made from folk music (if they could get around the fact that most of it is public domain), promoters began putting on multi-performer concerts (performers on stage, audience sitting in theater seats) and, in the manner of such carpetbaggers everywhere, they picked up the jargon without knowing or caring what it really means and called them "hootenannies." In 1963, ABC television started a half-hour program on Saturday nights featuring four acts in each show, and they called it "The ABC Hootenanny."

I make no comment about the quality of the performances;   that's another discussion. What I take issue with is the terminology. The shows were not "hootenannies." They were multi-performer concerts. But because this was their first exposure to the term, lots of people thought, and still think, that this is what a hootenanny is, and thus another perfectly good term gets usurped and corrupted by the forces of commercialism.

As Deckman says, with rare exceptions, "hoots" are held in private homes. If it's held in a hall or theater, and/or if you have to pay to get in, and/or if you can't bring your own guitar, banjo, nose-flute, or musical saw and jump in when the spirit moves you—it most emphatically is NOT a hootenanny, at least not the way the word was "traditionally" used.

Some people may quibble and squawk at this, but that, folks, is how and where the word got started. But words change with usage, and dictionaries often tend to reflect this. Merriam-Webster now defines "hootenanny" as "a gathering at which folksingers entertain often with the audience joining in." So I guess I'm tilting at windmills.

Don Firth

P. S. Etymology : Prior to its application to the folk music context, the word "hootenanny" was one of those made up terms like "thingamajig" or "whatchacallit" that people would use if they couldn't think of the correct word for something. Specifically, a "hootenanny" was defined as "a noisy contrivance of doubtful utility." Some unknown Seattle folky in the Thirties or Forties thought the term was appropriate for folk singers' get-togethers, started using that way, and Pete and Woody picked it up from there.