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Clock

Definition(s):

  A device that generates periodic, accurately spaced signals for timekeeping applications. A clock consists of at least three parts: an oscillator, a device that counts the oscillations and converts them to units of time interval (such as seconds, minutes, hours, and days), and a means of displaying or recording the results.
Source(s):
NISTIR 8323 from NIST T&F Glossary