Mr. Big

American  

noun

Slang.

1. a man having the highest authority, control, prestige, or influence in a group, field, situation, or the like, especially in the underworld.

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Mr Big British  

noun

1. slang the head of an organization, esp of a criminal organization

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Etymology

Origin of Mr. Big

First recorded in 1935–40

Example Sentences

Known by the nickname “Mr. Big Shot,” Billups made five All-Star teams.

From The Wall Street Journal

Mr. Big’s exit hurt, but it did not assault our eyeballs.

From Salon

“You” performer Camp did mention that she was an actor, but Mr. Big didn’t follow up.

From Los Angeles Times

The chat started with a question about their worst dates then segued into Mr. Big asking what the two expect from a guy on a first date.

From Los Angeles Times

"We think that the 'Mr Big' is probably a faceless commuter. I do not know him."

From BBC