put one's money where one's mouth is
Definition from Wiktionary, the free dictionary
- To make or take a bet.
- (idiomatic) To take an obvious stake in the truth of a claim that one is making.
2011 September 23, Jason Palmer, “Light speed: Flying into fantasy”, BBC News:
- "The scientists are right to be extremely cautious about interpreting these findings," said Jim Al-Khalili, a physicist from the University of Surrey, who suggested that a simple error in the measurement is probably the source of all the fuss..."So let me put my money where my mouth is: if the Cern experiment proves to be correct and neutrinos have broken the speed of light, I will eat my boxer shorts on live TV."