The paradox deals with the made-up words "autological" and "heterological". A word is called autological if it applies to itself. For example "short" is autological, since the word "short" is short. "Sophisticated" is also autological. Words that are not autological are called heterological. "Long" is a heterological word, for example. The obvious question arises: is "heterological" heterological? There is no consistent answer: if it is, then it isn't; if it isn't, then it is -- think it through.
More examples of heterological words: