If you have a big enough dictionary, just about everything is a word.
XML is not a language in the sense of a programming language any more than sketches on a napkin are a language.
Many computer scientists have fallen into the trap of trying to define languages like George Orwell's Newspeak, in which it is impossible to think bad thoughts. What they end up doing is killing the creativity of programming.
English poetry begins whenever we decide to say the modern English language begins, and it extends as far as we decide to say that the English language extends.
The American constitutions were to liberty, what a grammar is to language: they define its parts of speech, and practically construct them into syntax
The character of our language defines us, and dictionaries say as much about us as about the way we speak.
From now on I will consider a language to be a set (finite or infinite) of sentences, each finite in length and constructed out ofa finite set of elements. All natural languages in their spoken or written form are languages in this sense.
Dictionaries are like watches, the worst is better than none and the best cannot be expected to go quite true.