In use by the 6th century. Presumably from the phrase īte missa est (“go, the dismissal is made”) (said by a priest to dismiss the congregation after the service), where missa is Late Latin and Vulgar Latin, for missiō (“dismissal”), from mittō (“to discharge, release”) (ultimately from Proto-Indo-European *meyth₂- (“to change; to exchange; to remove”)) + -tiō (suffix attached to verbs forming nouns relating to actions or their results). An older derivation (16th century, attributed to Luther) adduced Hebrew מַצָּה (matsá, “unleavened bread; oblation”) (compare English matzo), but this is no longer considered a tenable etymology.