put your shirt on something
put (one's) shirt on (something)
1. To bet or risk everything one has on something. Tech companies seem to be putting their shirts on virtual reality being the future of the industry, but there are plenty who think that's a foolish stance to take. Anyone with a gambling addiction knows the feeling of putting your shirt on a hand of cards, feeling sure it will pay off big time, only to lose everything.
2. By extension, to be absolutely certain that something will happen. I would hope that the industry is moving towards a more customer-friendly position, but I wouldn't put my shirt on it.
put your shirt on somethingmainly BRITISH
If you put your shirt on something, you bet or risk a large amount of money on it, because you are certain that it will win or succeed. I was just thinking you might put your shirt on Golden Boy. It's bound to be a winner, isn't it? Note: You can also say that you lose your shirt, meaning you lose all your money on a bad investment or bet. His father warned him that he knew nothing about shipping and could easily lose his shirt. If you play cards with the big boys, you can lose your shirt.