The Collaborative International Dictionary of English v.0.48:

zine \zine\, 'zine \'zine\(z[=e]n), n. [shortened from
   magazine.]
   A publication similar to a magazine[4] but in electronic
   rather than printed form, maintained as data files on a
   computer and accessible via the world wide web; sometimes
   called e-zine ("e" standing for electronic, as in e-mail.
   [PJC]

The Free On-line Dictionary of Computing (30 December 2018):

electronic magazine
e-zine

    (e-zine) A regular
   publication on some particular topic distributed in digital
   form, chiefly now via the web but also by
   electronic mail or floppy disk.  E-zines are often
   distributed for free by enthusiasts.

   (1996-08-04)