My quick references contradict you on the way you relate it to the west.
“Ghost” comes from Germanic, “Gheist” which is related to “vision.” (Hence, the Catholic Church decided that “Holy Spirit” was a better than “Holy Ghost,” even though previously, a spirit could be animal, not rational (human). The sanskrit origin of “Ghost” was “hedah,” meaning wrath (anger).
I don’t read Hindu, but Wikipedia claims tantra is found in several veda... and established in the mainstream writings by 500 BC. Is it wrong?
First of all, most dictionaries ignore or don’t know Sanskrit roots. I know this for a fact. Sanksrit has many words for “ghost”, as there are many catebories. Ghora in Sanskrit means “horrible, frightening” etc, akin to the English word “ghastly” which is related to the word “ghost”.
Second, “Tantra” merely means “procedures” or “rituals”. There is Saivite Tantra, Vaishnava Tantra, etc. The Vama tantra as portrayed here dates from around the 1100s. Wikipedia is not necessarily the best source for authentic Hinduism.
I didn’t know that much about the origin and some of the more repulsive practices of Vama Tantra until I did some research on it about 5 years ago.