Original: Present or existing from the beginning.
Neither Space Mountain nor Matterhorn are original attractions. They are classic attractions (subjective) but not original. This isn't semantics, now if you'll excuse me I need to get back to my hair-brained ideas.
Indeed. People really mean "unique" or "particular" or "iconic" when they misuse "original." Original meaning 'first' or 'from the start' is used in "Original Sin" and "to originate". The phrase "it's an original" should only be used for the thing that started it all, not for something unique.
And....... it's "hare-brained." As in "mad as a march hare" to bring it around to an appropriated Disney property.