Term for person who conducts illegal business

What is the term for a person who conducts illegal business? Surely it is not illegal businessman, but maybe that could work.

It will be in any case a criminal, maybe a career criminal. When it goes to drug business, you call it a druglord, which in himself is a kind of kingpin. You can choose your poison.

But in the end, without contest, the word which would best fit your definition is a racketeer, although career criminal or illegal businessman are not bad themselves.

I think crook suggests the idea of illegal business better than criminal; a criminal is anyone who commits/is convicted of committing a crime, which is too broad IMHO.

Depending on the illegal business in question, there may be more contextual suggestions...

A white-collar criminal

is someone who commits crimes involving business activities, mostly desk-work crimes like accounting or insurance fraud.