nybble: /nibīl/, nibble, n.

[from v. nibble by analogy with ‘bite’ → ‘byte’] Four bits; one hex digit; a half-byte. Though ‘byte’ is now techspeak, this useful relative is still jargon. Compare byte; see also bit. The more mundane spelling “nibble” is also commonly used. Apparently the ‘nybble’ spelling is uncommon in Commonwealth Hackish, as British orthography would suggest the pronunciation /ni:ībl/.

Following ‘bit’, ‘byte’ and ‘nybble’ there have been quite a few analogical attempts to construct unambiguous terms for bit blocks of other sizes. All of these are strictly jargon, not techspeak, and not very common jargon at that (most hackers would recognize them in context but not use them spontaneously). We collect them here for reference together with the ambiguous techspeak terms ‘word’, ‘half-word’, ‘double word’, and ‘quad’ or quad word; some (indicated) have substantial information separate entries.

2 bits:crumb, quad, quarter, tayste, tydbit, morsel
4 bits:nybble
5 bits:nickle
10 bits:deckle
16 bits:playte, chawmp (on a 32-bit machine), word (on a 16-bit machine), half-word (on a 32-bit machine).
18 bits:chawmp (on a 36-bit machine), half-word (on a 36-bit machine)
32 bits:dynner, gawble (on a 32-bit machine), word (on a 32-bit machine), longword (on a 16-bit machine).
36 bits:word (on a 36-bit machine)
48 bits:gawble (under circumstances that remain obscure)
64 bits:double word (on a 32-bit machine) quad (on a 16-bit machine)
128 bits:quad (on a 32-bit machine)

The fundamental motivation for most of these jargon terms (aside from the normal hackerly enjoyment of punning wordplay) is the extreme ambiguity of the term word and its derivatives.