IPA: /ɪnˈdɪfərəntɪst/
KK: /ɪnˈdɪfərəntɪst/
A person who supports the idea that all religions or beliefs are equally valid and should be treated the same.
As an indifferentist, she believed that no single religion held the ultimate truth over others.
Indifferentist → It is formed from "in-" (meaning not) and "different" (from Latin "differens", meaning differing or distinct) and the suffix "-ist" (meaning one who practices or is concerned with). The word refers to a person who is not concerned with differences or distinctions, particularly in a philosophical or religious context.
Think of someone who is 'not' ('in-') concerned about 'differences' — that's what an indifferentist is.