From TheJargon Dictionary:
boxen /bok'sn/ pl.n. [very common; by analogy with VAXen] Fanciful plural of box often encountered in the phrase `Unix boxen', used to describe commodity Unix hardware. The connotation is that any two Unix boxen are interchangeable.
VAXen /vak'sn/ n. [from `oxen', perhaps influenced by `vixen'] (alt. `vaxen') The plural canonically used among hackers for the DEC VAX computers. "Our installation has four PDP-10s and twenty vaxen." See boxen.
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