A woman who marries a man for money, then kills him to inherit all that he has. She becomes a widow when he dies, and the black represents the dirty deed that she did.
Tom: Look at Michelle, dude! She's 25 and look how rich she is!
Daniel: I heard that she's a black widow, Tom, I wouldn't go near her!
Tom: What's a black widow?
Daniel: A woman who kills a man after marrying him for money.
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