The term Long Clock is not commonly used in the furniture industry. It is more commonly associated with the term longcase clock or grandfather clock. A longcase clock is a large, freestanding clock with a pendulum and weights housed in a tall, narrow case. It typically has a long, swinging pendulum and a set of chimes or a striking mechanism that indicates the time. The term long refers to the height of the clocks case. Grandfathers, hall, or tall clock.