Per [Oxford Dictionaries](https://en.oxforddictionaries.com/definition/cartel), a Cartel is 

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> **An association of manufacturers or suppliers with the purpose of maintaining prices at a high level and restricting competition**.
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The example given is *the Colombian drug cartels*.

While this definition does seem to fit a number of modern organisations, like telecom providers or health insurance providers in the US, it doesn't seem to fit with what I know of the practices of the drug cartels. These are illegal organisations which compete with one another, and the price of drugs is kept high by the fact that they're illegal, not by collusion between the cartels.

So what I'd like to know is how the name **Cartel** came to be associated with illegal drug suppliers, to the extent that many people define **Cartel** as exclusively a drug-running organization?