smoking gun

noun

1. indisputable proof or evidence of a crime.

smoking gun

noun

1. a piece of irrefutable incriminating evidence

Word History and Origins

Origin of smoking gun¹

First recorded in 1970–75

Idioms and Phrases

Something that serves as indisputable evidence or proof, especially of a crime. For example, There is no smoking gun in the Oval Office; the President had no role in tampering with the evidence . This expression alludes to the smoke coming from a recently discharged firearm, a normal occurrence until the invention of smokeless powder. [Mid-1900s]

Example Sentences

The concept is that the use of human embryonic cells in the manufacture of vaccines is the smoking gun—a major cause of autism.

From The Daily Beast

It was an interesting piece of information for those watching the investigation closely—but nowhere approaching a smoking gun.

From The Daily Beast

For them, the smoking gun was the personality—not the smokes.

From The Daily Beast

Within the 907 documents Wildstein turned over was a smoking gun.

From The Daily Beast

To an extent, but I think only to an extent—because if he is exonerated, it will happen only because no one found a smoking gun.

From The Daily Beast

He was a good judge of men, that eagle-faced major; he knew that the slightest move with hostile intent would mean a smoking gun.

From Project Gutenberg

With a proud smile the old woman stood the smoking gun against the wall and straightened her cap.

From Project Gutenberg

Jim thrust his smoking gun into his belt and caught Craig by the arm.

From Project Gutenberg

He looked up and beheld the girl about whom he had been thinking, every muscle tense, a smoking gun still against her shoulder.

From Project Gutenberg

He saw Campbell standing on the hill waving his still smoking gun.

From Project Gutenberg