'over-the-counter' originates from the practice of selling goods directly from a counter in a store, where 'over' indicates the transaction happening across the counter.

The term 'over-the-counter' evolved from the literal act of selling goods over a counter in a shop to its current financial and pharmaceutical meanings.

Initially, it referred to the physical act of selling goods across a counter, but now it also refers to non-prescription drugs and direct financial transactions.