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noun \ˈkläk\

Definition of clock

  1. 1 :  a device other than a watch for indicating or measuring time commonly by means of hands moving on a dial; broadly :  any periodic system by which time is measured

  2. 2 :  a registering device usually with a dial; specifically :  odometer

  3. 3 :  time clock

  4. 4 :  a synchronizing device (as in a computer) that produces pulses at regular intervals

  5. 5 :  biological clock

against the clock
  1. 1 :  with or within a time constraint <working against the clock>

  2. 2 :  with clocked speed rather than the order of finish as the criterion for placement <trial races against the clock>

around the clock also round the clock
  1. 1 :  continuously for 24 hours :  day and night without cessation

  2. 2 :  without relaxation and heedless of time

kill the clock or run out the clock
  1. :  to use up as much as possible of the playing time remaining in a game (as football) while retaining possession of the ball or puck especially to protect a lead

Origin of clock

Middle English clok, from Middle Dutch clocke bell, clock, from Old French or Medieval Latin; Old French dialect (Picard) cloque bell, from Medieval Latin clocca, of Celtic origin; akin to Middle Irish clocc bell

First Known Use: 14th century




Simple Definition of clock

  • : to measure the amount of time it takes for (a person) to do something or for (something) to be completed

  • : to finish a race in (an amount of time)

  • : to measure or show (the speed of something) with a measuring device

Full Definition of clock

  1. transitive verb
  2. 1 a :  to time with a stopwatch or by an electric timing device b :  to be timed at

  3. 2 :  to register on a mechanical recording device <wind velocities were clocked at 80 miles per hour>

  4. 3 :  to hit hard

  5. 4 chiefly British :  attain, realize —usually used with up <just clocked up a million … paperback sales — Punch>

  6. 5 a :  to travel (a distance) over time <clocks more than 15,000 miles a year on business> b :  put in 3 <clocking long hours at the office>

  7. intransitive verb
  8. 1 :  to have a specified duration or speed —used with in <the movie clocked in at just under 3 hours>; broadly :  to have a specified measure or value —used with in <the meal clocked in at about $15>

  9. 2 :  to register on a time sheet or time clock :  punch —used with in, out, on, off <he clocked in late>

clock·er noun

Examples of clock

  1. He clocked 3 hours and 15 minutes in his last marathon.

  2. His fastest pitch was clocked at 91 miles per hour.

  3. The cop said she clocked me going 95 miles per hour.

  4. I was so angry I wanted to clock him.


First Known Use of clock





Definition of clock

  1. :  an ornamental figure on the ankle or side of a stocking or sock

Origin of clock

perhaps from 1clock

First Known Use: 1530

Medical Dictionary


noun \ˈkläk\

Medical Definition of clock

Seen and Heard

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February 6, 2016

an official order, decree, or edict

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