octal

American  

[ok-tl] / ˈɒk tl /

adjective

1. Also 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.

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noun

1. octonary.

octal Scientific  

/ ŏk′təl /

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.

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Etymology

Origin of octal

First recorded in 1935–40; oct- + -al ¹

Example Sentences

“You’d punch one number wrong into a card, and you got a bunch of wasted paper … just a bunch of octal numbers that didn’t mean anything.”

From Scientific American • Jul. 12, 2019

The index address, X, is in octal digits 3, 4, and 5.

From Preliminary Specifications: Programmed Data Processor Model Three (PDP-3) October, 1960 by Digital Equipment Corporation

Once upon a time, these magic numbers were PDP-11 branch instructions that skipped over header data to the start of executable code; the 0407, for example, was octal for `branch 16 bytes relative'.

From The Jargon File, Version 2.9.10, 01 Jul 1992 by Raymond, Eric S.

The left half of these registers is available for the storage of constants, tables, etc., when octal digits 7 through 11 act as index registers.

From Preliminary Specifications: Programmed Data Processor Model Three (PDP-3) October, 1960 by Digital Equipment Corporation

The first bit of octal digit 2 is the indirect address bit.

From Preliminary Specifications: Programmed Data Processor Model Three (PDP-3) October, 1960 by Digital Equipment Corporation