Dimethyltryptamine - a naturally occurring psychedelic compound of the tryptamine family. 'Deemur' most commonly refers to 5-MeO-DMT, the most potent form of dimethyltryptamine, which can be chemically synthesized or extracted from the venom of certain frogs.
DMT is one of the most potent psychadelics, causing a range of effects from short-lived milder psychedelic states to powerful immersive experiences, which include a total loss of connection to conventional reality, which may be so extreme that it becomes ineffable.
DMT is commonly insufflated (inhaled/snorted) or consumed orally. DMT can also be extracted from various natural plant sources (psychotria viridis and momosa hostilis, most commonly) and combined with an MAOI-containing materials (such as syrian rue) and is brewed as a tea called 'ayahuasca' and drunk, causing the same dissociative effects as well as extreme nausea and vomiting.
A form of dimethyltryptamine is also found in psychadelic mushrooms (psilocin - 4-hydroxydimethyltryptamine), but is not usually referred to by the common DMT street names, as it is not commonly known that psilocybin/psilocin is DMT-based.
"Hey dude, you got some deemur?"
"Hell yes, we're gonna blast the fuck off tonight."