A clock is a device that keeps time, displaying hours, minutes, and often seconds. If there's a clock in your calculus classroom, it can sometimes be hard to keep from watching the minutes tick by.

You might have an antique grandfather clock in your hall or an alarm clock beside your bed. Clocks are either analog, with hands that move around a numbered circular face, or digital, showing the time in digits, like 4:27. If you clock your friend as she runs a mile, it means you keep track of how long it takes her. Originally, the word was clokke, "clock with bells," from the Medieval Latin clocca, "bell."

Definitions of clock
  1. noun
    a timepiece that shows the time of day
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    Big Ben
    clock in the clock tower of the Houses of Parliament, London
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    alarm, alarm clock
    a clock that wakes a sleeper at some preset time
    analog clock
    a clock that displays the time of day by the position of hands on a dial
    an accurate clock (especially used in navigation)
    cuckoo clock
    clock that announces the hours with a sound like the call of the cuckoo
    digital clock
    a clock that displays the time of day digitally
    electric clock
    a clock using a small electric motor
    pendulum clock
    a clock regulated by a pendulum
    system clock
    a time-of-day clock in a computer system
    time clock
    clock used to record the hours that people work
    turret clock
    a clock with more than one dial to show the time in all directions from a tower
    wall clock
    a clock mounted on a wall
    clepsydra, water clock, water glass
    clock that measures time by the escape of water
    grandfather clock, longcase clock
    a pendulum clock enclosed in a tall narrow case
    type of:
    horologe, timekeeper, timepiece
    a measuring instrument or device for keeping time
  2. verb
    measure the time or duration of an event or action or the person who performs an action in a certain period of time
    “he clocked the runners”
    synonyms: time
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    time incorrectly
    type of:
    measure, quantify
    express as a number or measure or quantity
Word Family

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