noun
Usually in plural. An issue or practice not considered to be central to a religion, especially Christianity; a religious matter that allows latitude; a non-essential element of a faith. Also: something of a morally neutral nature; a thing which is neither inherently good nor bad.
Frequently with reference to the practices considered as adiaphora by the moderate Lutherans in 16th century. Germany.
adjective
In predicative use. Of the nature of an adiaphoron or adiaphora.
Origin
Mid 16th century; earliest use found in Richard Taverner (?1505–1575), translator and evangelical reformer. From post-classical Latin adiaphoron (usually in plural, adiaphora) from ancient Greek ἀδιάϕορον (usually in plural, ἀδιάϕορα), something neither good nor bad, use as noun of neuter of ἀδιάϕορος indifferent.