| a pendulum floor clock having a case as tall as or taller than a person; tall-case clock; long-case clock. |

| grandfather clock n. A pendulum clock enclosed in a tall, narrow cabinet. [From the song My Grandfather's Clock by Henry Clay Work (1832-1884), American songwriter.] |
grandfather clock
tall pendulum clock enclosed in a wooden case that stands upon the floor and is typically 1.8 to 2.3 metres (6 to 7.5 feet) in height. The name grandfather clock was adopted after the song Grandfather's Clock, written in 1876 by Henry Clay Work, became popular. The first grandfather clocks featured a Classical architectural appearance, but a variety of styles have enjoyed popularity over the years. One form of early pendulum clock was wall-mounted but, because of its heavy lead weights, probably difficult to secure. It is believed that the grandfather clock was developed to support these heavier clock mechanisms
Learn more about grandfather clock with a free trial on Britannica.com.