frobnitz /frob'nits/, plural `frobnitzem' /frob'nit-zm/ or `frobni' /frob'ni:/ [TMRC] n. An unspecified physical object, a widget. Also refers to electronic black boxes. This rare form is usually abbreviated to `frotz', or more commonly to frob. Also used are `frobnule' (/frob'n[y]ool/) and `frobule' (/frob'yool/). Starting perhaps in 1979, `frobozz' /fr*-boz'/ (plural: `frobbotzim' /fr*-bot'zm/) has also become very popular, largely through its exposure as a name via Zork. These variants can also be applied to nonphysical objects, such as data structures.

Pete Samson, compiler of the original TMRC lexicon, adds, "Under the TMRC [railroad] layout were many storage boxes, managed (in 1958) by David R. Sawyer. Several had fanciful designations written on them, such as `Frobnitz Coil Oil'. Perhaps DRS intended Frobnitz to be a proper name, but the name was quickly taken for the thing". This was almost certainly the origin of the term.