Words: adiaphoron
Part of speech: n
Definition: a religious ceremonial or ritual observance that is held to be an affair of the individual conscience because it is neither forbidden nor enjoined by the scriptures.
Example: For all of the wild-eyed (and completely sectarian) assertions floating around the LCMS that ordination is a mere adiaphoron, that "laying on of hands" does not mean ritual ordination but rather a democratic election, that ordination confers nothing - I have yet to ever read about anyone actually graduating seminary and taking a call to a congregation and choosing to forgo the rite of ordination.