Mala hierba

Question

Okay, I know this literally translates to "a weed," but what is a good translation of its idiomatic meaning? Is it region-dependent? While we're at it, is there an English equivalent of "mala hierba nunca muere" (I know what it means literally.)
For that matter: "mala leche"--same question.

Answer 1

"Mala hierba" is usually used as "bad person". There is a common saying in Argentina: "Hierba mala nunca muere" usually applied to people.
"Mala leche" means malice. You say : "Lo hizo con mala leche", meaning that an action was not ment to be good.

Answer 2

I think mala hierba can mean drugs, like dope or weed, it can also mean like a bad seed, or a bad person. I believe that the same goes for mala leche, or bad milk.

Ana

Answer 3

Useless would probably be the best 'universal' meaning. Mala hierba - useless herb aka weed, mala leche - useless milk, aka spoiled milk.

Answer 4

That reminds me of that song by Alejandra Guzmán. I checked on another website (WR) and someone suggested "bad seed."