An alternative pluralization of boxes. In 60-80s hacker lingo (when hacker ment something very different, btw), it originated from vax/vaxen (the, at the time, correct way to referr to two or more vax computers). Because of this unusual pluralization, it because common to use -en instead of -es or whatever else was correct for all words ending in x or with an x sound, such as soxen or socksen for more then one sock. Box was/is usually referring to a computer (pc, server, workstation, whatever).

Got the covid-19 vaccine

Plural for box or computer. Usually PCs.

THE PLURAL OF OX IS OXEN SO THE PLURAL OF BOX IS BOXEN

alternate pluralization of the singular noun "box," as opposed to the correct "boxes," made famous by comedian brian reagan

More than one computer box. From the pluralization of "ox", i.e.:

one ox, two oxen
one box, two boxen

The Plural for Box, Stated by Brian Regan in his "Stupid In School" Standup,

Country of origin: Brian Regan in Grade School