Orthodoxy — from Greek, orthodoxos, from orthos, “right,” and doxa, “belief”

Ideas held to be the standard of right belief. A standard of orthodoxy may be established by authority (the judgment of others), tradition (the test of time), testimony (written documentation), or reason (personal experience).

Heterodoxy — from Greek, heteros, “other,” and doxa, “belief”

Those beliefs outside or counter to the accepted body of teaching.

Heresy — from Greek, hairesis, “choice”

A view chosen instead of the official teaching of a church, which is thus considered wrong or potentially dangerous.