triplenibble

Triplenibble is an informal term used in computing to refer to a group of three consecutive 4-bit units, i.e., a 12-bit block. It is not an official data unit, but a descriptive convenience in discussions about data packing, memory layout, or vintage computing where 12-bit quantities arise.

Three nibbles equal 12 bits. The triplenibble can encode values from 0 to 4095 (0x000 to 0xFFF). Because it spans 12 bits, it does not align neatly with standard 8-bit bytes and is sometimes stored as 1.5 bytes or packed with adjacent fields in a bitfield. In practice, representations of a triplenibble can vary depending on endianness and the surrounding data structure.

Usage and relevance: In some retro or hobbyist architectures, triplenibbles appear in color palettes, character encoding schemes, or memory-addressing schemes that predate or eschew full bytes. It is also used descriptively in software and hardware documentation to denote compact data fields that are 12 bits wide. The term remains uncommon in formal specifications and is largely contextual, sometimes differing in how adjacent fields are packed or interpreted.

See also nibble, byte, word, 12-bit data. Because triplenibble is nonstandard, definitions and examples may vary between sources and applications.