dimethyltryptamine (da??mi??a?l?tr?pt?m?n; -?m???l-) n (Elements & Compounds) a hallucinogenic agent that may trigger the onset of psychosis or emotional problems in predisposed individuals. Abbreviation: DMT Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014