binary system

American  

noun

1. a system involving only two elements, as 0 and 1 or yes and no.

2. Mathematics. a system of counting or measurement whose units are powers of two.

3. Astronomy. binary star.

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Etymology

Origin of binary system

First recorded in 1825–35

Example Sentences

In a typical binary system, two stars with slightly different masses circle each other along elongated, or elliptical, paths.

From Science Daily • Apr. 19, 2026

Though he takes a minute to upbraid her, they’re obviously the show’s binary system, and Decker is in any case a cheery sort who takes things in stride — even prison, seemingly.

From Los Angeles Times • Mar. 3, 2026

"The evidence strongly supports a binary system containing a magnetar -- a neutron star with an extremely strong magnetic field, and a star like our Sun."

From Science Daily • Jan. 28, 2026

This strange new world orbits around two stars at once, which dance around each other in what astronomers call a binary system.

From Space Scoop • May 6, 2025

The spectroscope shows that the brighter of these stars is again a binary system of two huge suns, the components revolving around each other in a period of about twenty days.

From Astronomy of To-day A Popular Introduction in Non-Technical Language by Dolmage, Cecil Goodrich Julius