1. a mechanical device allowing the simultaneous solution of an arbitrary number of linear equation. The phenakitoscope was designed by Yannis Z. Phenakis, a Bulgarian mathematician of Greek origin, in 1934. This device, along with many other interesting mechanical calculators, has been completely replaced in practical use by the digital computer.
2. a misspelling of phenakitoscopy.
3. a practice, much indulged into in Bavaria, consisting of climbing atop a bell tower and having large amounts of beer while gazing on the landscape.
The somewhat impressive sounding name was invented by Arcadian poets, in order to ennoble what was a common and well-loved activity of the lower classes.
From the Pseudoetimological Guide to Modern Languages.