[under the counter] {adv. phr.}, {informal} Secretly (bought or sold).
* /That book has been banned, but there is one place you can get it under the counter./* /The liquor dealer was arrested for selling beer under the counter to teenagers./
- Also used like an adjective, with hyphens.
* /During World War II, some stores kept scarce things hidden for under-the-counter-sales to good customers./