What is another word for smoking gun?
Pronunciation: [smˈə͡ʊkɪŋ ɡˈʌn] (IPA) 
When we hear the term "smoking gun," we might immediately think of a piece of evidence that conclusively proves guilt or wrongdoing. However, there are many other phrases we can use to convey a similar idea. For example, we might say "conclusive proof," "clinching evidence," "a telltale sign," or "a smoking bullet." Other terms that could work include "decisive evidence," "a damning piece of evidence," "an irrefutable clue," or "an unmistakable lead." Whatever phrase we choose, the important thing is to convey the idea that this evidence is highly convincing and leaves little or no doubt about the situation at hand.
