VAX /vaks/ n. 1. [from Virtual Address eXtension] The most successful
   minicomputer design in industry history, possibly excepting its
   immediate ancestor, the PDP-11. Between its release in 1978 and its
   eclipse by {killer micro}s after about 1986, the VAX was probably the
   hacker's favorite machine of them all, esp. after the 1982 release of
   4.2 BSD Unix (see {BSD}). Esp. noted for its large,
   assembler-programmer-friendly instruction set -- an asset that became a
   liability after the RISC revolution. 2. A major brand of vacuum cleaner
   in Britain. Cited here because its sales pitch, "Nothing sucks like a
   VAX!" became a sort of battle-cry of RISC partisans. It is even
   sometimes claimed that DEC actually entered a cross-licensing deal with
   the vacuum-Vax people that allowed them to market VAX computers in the
   U.K. in return for not challenging the vacuum cleaner trademark in the
   U.S.

   A rival brand actually pioneered the slogan: its original form was
   "Nothing sucks like Electrolux". It has apparently become a classic
   example (used in advertising textbooks) of the perils of not knowing the
   local idiom. But in 1996, the press manager of Electrolux AB, while
   confirming that the company used this slogan in the late 1960s, also
   tells us that their marketing people were fully aware of the possible
   double entendre and intended it to gain attention.

   And gain attention it did - the VAX-vacuum-cleaner people thought the
   slogan a sufficiently good idea to copy it. Several British hackers
   report that VAX's promotions used it in 1986-1987, and we have one
   report from a New Zealander that the infamous slogan surfaced there in
   TV ads for the product in 1992.


Source: The Jargon File

VAX
     Virtual Address eXtension (DEC, VAX)
     
     
Source: Virtual Entity of Relevant Acronyms