I thought it could be espam of an alcoholic drink prepared with herbs, seeds and other components of vegetable origin, which according to its manufacturers has Greek origin and etymology, but they do not explain from which word it comes; And it seems to me that there is something of the Swahili Majuni, which is related to the leaves, to the petals and by extension to the medicine prepared with plants. But digressions aside, from the synonyms provided by my colleague Sergio M, I suppose it is a localism as a more familiar and humorous version (perhaps influenced by Arabic) of majo ("nice, beautiful, funny").
