@MariaATX
Well, a rather complex (at least still for me) mathematical term, that describes a part of or a topological space, that resembles what is called Euclidean space near each point, and have some homeomorphic neighbourhood. So in short, I suppose it is a nerd topological thingy.

Thanks for answering. May I ask what your book is about?

Best of wishes
Regards

Hmmm.... Complex for me too! My book is a hard boiled detective story (why I am reading it — I love the genre) but past that’s i cAnt day yet @AllAboutTheFacts