grandfather's clock

or grandfather clock

Origin of grandfather's clock

First recorded in 1890–95
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for grandfather clock

grandfather clock

noun
  1. any of various types of long-pendulum clocks in tall standing wooden cases, usually between six and eight feet tallAlso called: longcase clock
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012