Derived either from Ender's Game or the streets of Winona, 'neh' is an interrogative statement meaning "isn't that so?". It also goes well with any other adopted lingo from Battle School graduates originating from Ender's jeesh. More often used in non verbal communication (e.g. instant messaging, email), 'neh' is a not well known term.

A term used to reference cannabis/marijuana/weed.

Largely used in Japan at the end of a sentence as a way of saying, "right?" or "isn't that so?" among other things. The book Shogun used it frequently, and it is commonly used in anime to this day.

The interjection "neh?" at the end of a sentence is equivalent to the Canadian "eh/hey?", or the British/Scots "innit?". Was invented neither by Orson Scott Card nor on the streets of Winona, Minnesota, but rather has been in the language for a good long time without too many people noticing. They still don't.

"Neh" is either a foreshortened loan of the French "n'est-ce pas?", or a direct loan of the Portuguese contraction "né?" (literally, "não é?"), which means the very same thing when placed at the end of a sentence. It is difficult to find any particular attribution to "neh" in English literature because it is vernacular and evolved as a spoken interjection, not to be written down.

No. It is a way of saying no with a degree of disgust or negativity

very similar to meh, but in negative indifference.

originated by the creator of the interjection meh

Portmanteau word
Neh: Nah and Meh