nibble

In computers and digital technology, a nibble (pronounced NIHB-uhl; sometimes spelled nybble) is four binary digits or half of an eight-bit byte. A nibble can be conveniently represented by one hexadecimal digit.

Like crumb, nibble carries on the "edible data" metaphor established with bit and byte.

In communications, a nibble is sometimes referred to as a "quadbit." or one of 16 possible four-bit combinations. A signal may be encoded in quadbits rather than one bit at a time. Nibble interleaving or multiplexing takes a quadbit or nibble from a lower-speed channel as input for a multiplexed signal on a higher-speed channel.