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The second is the SI unit of time. Its name comes from being the "second" division of the hour, with the minute being the first.[1] It's not a coincidence that 'second' the time unit looks like 2nd, because it isn't the first division it's the second. Minute actually looks like the word for very small because it has the same root (also the same as minutia).

Prof. Rowlett has a unit dictionary, where he has several interesting things to say about units of time see for example:

  • the second
  • the minute = 60 seconds
  • the hour = 60 minutes = 3600 seconds
  • the solar day, and the sidereal day. The solar day = 24 hours = 1440 minutes = 86400 seconds
  • the year = 31,500,000 seconds (roughly pi * 10 million if you need an easy conversion)
  • the century = 100 years
  • the millennium = 1000 years


  1. R. Rowlett, UNC Chapel Hill. (2008). How Many? A Dictionary of Units of Measurement [Online]. Available:

Authors and Editors

Jordan Hanania, Braden Heffernan, James Jenden, Jason Donev
Last updated: June 4, 2018
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