Code word for expressing the fact that you can't talk about something now because a person that it might offend is within earshot and you can talk about it later.
Yeah, Mike, do you have any....Whoa, jumongo.(Mike knows that you are not asking him because your mom just walked in)
A general feeling or vibe, usually negative (bad ju-ju). Can be used in reference to karma, etc.
I'm getting some bad ju-ju from that cop. I think he's going to arrest me.
OR
I'm not surprised I broke my arm; I've still got some bad ju-ju from that time I hacked xyz.com.