Etymology of the Greek word amethustos (ἀμέθυστος)
the Greek word amethustos, ἀμέθυστος (the 'amethyst' (supposed to prevent intoxication))
using the Greek prefix a-, ἀ- (an- not, without)
derived from the Greek word methuein, μεθύω (to drink to intoxication; get drunk)