Initially actually N10, for the Intel i860 CPU. I think “New Technology” came from marketing then.

If you watch the interview with David Cutler to the time code I linked to, he explains that NT stands for New Technology which marketing did not want.

In which he specifically says that there may have been some point, early on, where it stood for N-10.

I just watched it. He does not say what you are maintaining he says.

One of my very favorite facts about Windows 2000, as revealed in its boot screen, is that it's based on New Technology Technology.

(I no longer work with Windows very much, but this little bit of trivia has stuck with me over the years)