noun

• (countable) A fetish or charm believed by West Africans to have magical or supernatural powers.
  "Pendants round the neck, bangles round the wrists or ankles, potatoes or nutmegs in the pocket are as old or older than civilisation, carrying the same prophylactic magic as any juju in an African witchdoctor's armamentarium."
• (uncountable) The magical or supernatural power of such a charm.
  "They are believed to be "Ju-Ju" or were-leopards, and in this guise to roam through the forest in bands, bent on evil and destruction."
• (informal) The (usually negative) karmic consequences of an action or behavior.
  "That's some bad juju."

noun

• (slang) A marijuana cigarette; a joint.
  "‘I knew a guy once who smoked jujus,’ she said. ‘Three highballs and three sticks of tea and it took a pipe wrench to get him off the chandelier.’"