What language does the term "Ayahuasca" originate from?

Answer 1

American Heritage® Dictionary: Description of ayahuasca
NOUN: A hallucinogenic brew made from the bark and stems of a tropical South American vine of the genus Banisteriopsis, especially B. caapi, mixed with other psychotropic plants, used especially in shamanistic rituals by certain Amazonian Indian peoples.
Wikipedia Dictionary:
Ayahuasca (Quechua, pronounced [a.ja.ˈwa.ska]) is any of various psychoactive infusions prepared from the Banisteriopsis spp. vine, native to the Amazon rainforest (which is also called ayahuasca). The resulting drinks are pharmacologically complex and used for shamanic, folk-medicinal, religious, and recreational purposes. Too, "ayahuasca" or "ayawaska" in Ecuador, Bolivia and Peru, also to a lesser extent in Brazil ("vine of the dead" or "vine of souls": In Quechua, aya means "spirit," "ancestor," or "dead person," while waska means "vine" or "rope"). Also known as "natem" amongst the indigenous Shuar people of Peru.
The spelling "ayahuasca" is the hispanicized version of the name; many Quechua or Aymara speakers would prefer the spelling ayawaska. In the central Andeans of Perú, Ayacwasca means :"Ayac" (spirit or dead) and "Wasca" (vine, cord or rope).

Answer 2

It is Quechua

Ayahuasca visions
The religious iconography of a peruvian shaman.

The Ayahuasca is an important hallucinogenic drink consumed by the native peoples of the western half of the Amazon valley and by isolated tribes of the Andes. The primary plant material used for this botanical brew is the bark of the giant forest liana Banisteriopsis caapi. This ayahuasca, as it is most commonly called, is prepared by boiling Banisteriopsis bark with the leaves of one or more admixture plants, most commonly Psychotria viridis. Although some aboriginal tribes have traditions of using Banisteriopsis solely, without any admixture plants, the predominant pattern of use has called for the addition of plants with diverse profiles of chemical constituents and psychoactive effects.

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