English definition of “clock”
/klɒk/ noun [C]
TIME › a piece of equipment that shows you what time it is, usually in a house or on a building: She could hear the hall clock ticking.
VEHICLE UK › a piece of equipment in a vehicle for measuring how far it has travelled: a car with 63,000 kilometres on the clock
around/round the clock › all day and all night: Rescue teams are working round the clock to search for survivors of the earthquake.
race/work against the clock › to do something as fast as you can in order to finish before a particular time → See also alarm clock → See also grandfather clock