1. Also octonary. of or relating to the number system with base 8, employing the numerals 0 through 7.
  2. relating to or encoded in an octal system, especially for use by a digital computer.
  3. (of an electronic device) having eight pins in its base for electrical connections.

Origin of octal

First recorded in 1935–40; oct- + -al1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

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octal in Science


  1. Relating to a number system having a base of 8. Each place in an octal number represents a power of 8. Octal notation has often been used in computer programming because three-digit binary numbers are readily converted into one-digit octal numbers from 0 to 7.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.