Over-the-counter (adjective)

1. Denoting a security or commodity that is traded outside a stock exchange.
2. Denoting medication that can be obtained without a prescription.

Origin:

Mid 19th century: from over-the-counter, denoting a transaction or purchase made across a counter.

Examples:

1. Over-the-counter drugs are available without a prescription.
2. Over-the-counter stocks are traded outside of traditional stock exchanges.
3. The company's over-the-counter drug sales have been increasing.
4. Over-the-counter trading is less regulated than exchange trading.
5. The over-the-counter market for foreign currencies is vast and decentralized.