It seems that, in order to stress an expression, we often use foreign terms for emphasis. Think of a word like voilà, which sounds so much more sophisticated than a mere “here you are” or, even worse, a triumphant “ta-dah!” The German term “nix” – same pronunciation as in English – is an even more interesting case, as here a pronoun is used as a pronoun, but it also can become a verb! Now, isn’t that wild?!
Nix is a common word in Germanic languages, by the way. In German it has been a colloquial contraction of the word “nichts” (pronounce neeh-ts), which means “nothing”, since the late 18th century. It is also used as an exclamation meaning “no way!”
Why ever it became a verb in English has to do with the very interesting linguistic fact that this language allows for hybrids and word creations of all kinds, either in using the word stem or in adding a syllable. Think of the noun “fence” and the verb “to fence in” or of the adjective “pretty” and the verb “to prettify” and the noun “prettification”. Even if a word doesn’t exist, we all understand somebody who makes up a word based on this simple rule.
This is how “nix” became a verb – it is obvious that something comes to nothing. To nix an order means to cancel it. To nix somebody’s plan means, in this case, to refuse to accept it. In other words, it comes to nix. Now, here is the pronoun. And, of course, you might as well say zilch, zero, nought, nothing, nada. Ooh, Spanish, even! Not to forget the expression “mox nix” – from German “macht nichts“ (pronunciation muh-t neeh-ts), meaning “it doesn’t matter”. My hunch tells me it might be Yiddish, though I also came across the explanation that American G.I.s brought back this Germanism to the States after WW II.
You may be surprised that there is an entirely unrelated meaning to the term nix in German. If used as a masculine noun, “Nix” is a fresh-water water spirit, half human, half fish, living in a splendid underwater palace. In Old English, the term “nicor” meant a water monster. In either language they are creatures not to be trusted. To be sure, if somebody told me about an encounter with a nix, I’d distrust the narrative as well. Even though we know that Ye Olde Curiosity Shop in Seattle holds a Fiji mermaid, the salty variety of a nix. A mermaid, of course, is not necessarily an evil spirit. As to the one in Seattle – one has to believe what one sees with one’s own eyes, right?