"one indifferent to religious creeds," c.1704, originally dismissive, from anything on model of trinitarian, unitarian, etc.
- anything but,
- anything goes,
- anything like,
Online Etymology Dictionary, © 2010 Douglas Harper
Examples from the Web for anythingarian
We all, from the Tractarian to the Anythingarian, are exactly of the same opinion.Plays and Puritans|Charles Kingsley