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

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

A nova happens in a close binary system when a white dwarf, the dense leftover core of a star, pulls gas from a nearby companion.

From Science Daily • Dec. 31, 2025

"This makes TOI-2267 the first binary system known to host transiting planets around both of its stars."

From Science Daily • Nov. 12, 2025

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

Sirius is also a binary system; but it is what is called a "visual" one, for its component stars may be seen separately in very large telescopes.

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