binary digit

noun, Mathematics, Computers.
1.
either of the digits 0 or 1 when used in the binary number system.
2.
bit3 (def 1).
Origin
1945-50
British Dictionary definitions for binary digits

binary digit

noun
1.
either of the two digits 0 or 1, used in binary notation See also bit4
binary digits in Science
binary digit  
Either of the digits 0 or 1, used in the binary number system. See more at bit.