binary
/ˈbaɪnəri/
/ˈbaɪˌnəri/
noun
The binary system: binary notation.
the device is counting in binary
adjective
Relating to, composed of, or involving two things.
testing the so-called binary, or dual-chemical, weapons
dual,duplex,twin,binary,duplicate,matched,matching,paired,in pairs,complementary,coupled,twofold