Dry ice refers to solid carbon dioxide, a substance that turns from a solid directly into a gas without becoming a liquid first. It is extremely cold and creates a smoky effect when it comes into contact with warmer objects. Full definition
To make ice last even longer, first place a bag of dry ice on the bottom of the cooler, cover it over with ice, and then place the food on top. (mindbodygreen.com)
We will ship your ice cream in an insulated cooler with dry ice so it will arrive to you still frozen. (wisechoicemarket.com)