Clock

A clock was an instrument for measuring time, sometimes utilising a clockwork mechanism.

Types of Clocks

The First Doctor kept an ormolu clock in the TARDIS control room. (DW: An Unearthly Child)
The Clockwork Droids used to break clocks to disguise their own ticking. (DW: The Girl in the Fireplace)
A spaceship crashed into "Big Ben", the clock tower of the Palace of Westminster. (DW: Aliens of London)
Jack Harkness parked his space craft by the clock tower of the Palace of Westminster. (DW: The Empty Child)
Bilis Manger ran a store called A Stitch in Time, where he sold clocks. (TW: End of Days)
The Institute for Technological Advancement and Research had a beryllium atomic clock for the countdown of the new millennium. (DW: Doctor Who (1996))

A crucial part of the Chameleon Arch looked like a fob watch. (DW: Human Nature, The Family of Blood, Utopia) Upon meeting Jackson Lake and seeing his fob watch, the Doctor thought that Jackson might be an incarnation of himself. (DW: The Next Doctor)

At times the Master's TARDIS took the shape of a grandfather clock. (DW: The Deadly Assassin/The Keeper of Traken)
In the Edwardian house Edward Grove, the chimes of a grandfather clock could be heard every time the time loop started over again. (BFA: The Chimes of Midnight)
Bilis Manger hid an important part of the Rift manipulator in a grandfather clock in his office. (TW: Captain Jack Harkness)