smoking gun 
noun
A piece of incontrovertible incriminating evidence: the trial’s long-awaited smoking gun failed to surface...
- Yes, I think ultimately the White House is going to have to show some concrete evidence, a smoking gun.
- We knew from the Columbia Investigation there were likely to be few smoking guns; the evidence was mostly public testimony and clarified during various news conferences during and after the hearings.
- Each new revelation was the smoking gun that was going to end his presidency.
- cosmic string
- cosmo-
- cosmodrome
- cosmogenesis
- cosmogenetic
- cosmogenic
- cosmogeny
- cosmogonic
- cosmogonical
- cosmogonist
- cosmogony
- cosmographer
- cosmographic
- cosmographical
- cosmography
- cosmological
- cosmological argument
- cosmological constant
- cosmologist
- cosmology
- cosmonaut
- cosmopolis
- cosmopolitan
- cosmopolitanise
- cosmopolitanism