It is a common over the counter mouth rinse, mine is called Dry Mouth oral rinse, this is from Dollar General but can be found in most stores Walmart included

I'm guess they are referring to a mouthwash designed for people who get dry mouth. I use Biotene brand. It also comes in a toothpaste too. I have dry mouth from some of my meds. Last summer I discovered the dry mouth also causes tooth decay! Huge expense and months of treatment.