a system involving only two elements, as 0 and 1 or yes and no.
a system of counting or measurement whose units are powers of two.
(for defs 1, 2).
a number system having a base of two, numbers being expressed by sequences of the digits 0 and 1: used in computing, as 0 and 1 can be represented electrically as
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They think it was part of a two-star or binary system.
If it actually is in the nebula, perhaps its one member of a former binary system, the other star being the one that exploded.
Both pulsars and bursters, astrophysicists have long thought, involve a binary system: two stars orbiting each other.
For one thing, the stars may have started life in a binary system, in a tight orbit around another star.
Binary system technologies offer both environmental advantages and disadvantages.