1. (

• methylenedioxymethamphetamine ,
• MDMA

) a stimulant drug that is chemically related to mescaline and amphetamine and is used illicitly for its euphoric and hallucinogenic effects; it was formerly used in psychotherapy but in 1985 it was declared illegal in the United States; "MDMA is often used at parties because it enables partygoers to remain active for long periods of time" ;