Hmm. That's a really interesting one.ph0yce said:So, would it be okay to put this word on a shirt?
Bear in mind I am not a lawyer and everything I'm saying here is conjecture and not legal advice.
The first thing I'll say is that it may be enough to get you sued. If you had the money you might win that case, but maybe you can't afford to get sued. I think it's one of the most important points that gets made on these forums - you can be within the law and still get sued, this can be costly even if you are in the right.
As for the topic itself...
Art has a history of borrowing and paying homage to itself. That is especially true in the genres of poetry and science fiction. Asimov's three laws of robotics are often used by other writers in their own stories; the character of Bester in Babylon 5 was named for the writer Alfred Bester and much of the ideas of how telepathy works in B5 are taken from his writings.
But then we have a few much more directly related examples: the words android, robot, cyborg and replicant. The word android was invented in the 19th century, so any possible claims to ownership have now ended. The other three are all inventions of the 20th century. Robot was coined for a play in 1921, cyborg by theoretical scientists in 1960, and replicant by a screenwriter working on Blade Runner in 1981.
What these words all have in common, to a greater or lesser extent, is that they've all fallen into common usage. With its 1921 coinage the word Robot has a good chance of being out of copyright now (were such a thing to apply) but clearly wasn't when it was being used extensively by others very soon after its first use. The word Cyborg also found itself quickly entering the mainstream SF lexicon, and from there the world at large's vocabulary.
The most recent, and so far least adopted, is the word Replicant. Even that has appeared in an anime series, a tv series, and is the title of a Jean-Claude Van Damme movie (I mean really).
I would suggest that if you want a test case that is a perfect example. Coined only 25 years ago, with a clear progenitor and current owner. Granted there is the possibility that the owner has the right to sue and has chosen not to, whereas others may not share that view regarding their words.
Did the people using the word Replicant pay royalties? It's possible. If so, that should give you an idea of where your boundaries lay.
My feeling, as a non-lawyer, is that you can't own a word unless you trademark it, and you can't trademark a science fiction word describing something that doesn't exist. Until you actually invent a replicant, patent the process, and trademark a new name for the product, the word is public domain. Imagine what life would be like if every time a new word was coined we had to get permission to use it? Language would fall apart. It's my feeling that that's not how the legal system operates. You can copyright long strings of words, you can trademark as little as a single word in connection with a product, but if you invent a word that you intend to use as part of the language, once invented it becomes public domain.
(a more interesting area then would be the Klingon language, which I would speculate would be under copyright)
One important thing to note, however, is that I'm talking about use of language in the context of either art, academia, or everyday life. But your intended use is a commercial application. While you might be able to use that word, since you are intending it to specifically refer to an anime series, you run the risk that the copyright holder can uphold a case that you are infringing on their intellectual property. They have exclusive rights to market products referring to their property - so your product is either 1) Infringing, or 2) Irrelevant. That's the theory anyway...
As usual, the real advice is to talk to a lawyer.