Troparion

The word probably derived from a diminutive of the Greek tropos ('something repeated', 'manner', 'fashion'), since the earliest function of the troparion was a refrain during the recitation of the cantica (biblical odes) and the psalms, as such the term was used as a synonym of hypakoe.

Today, since the redefinition of the Octoechos according to the hyphos of Constantinople, the monodic form of Orthodox chant distincts the troparic (apolytikia, theotokia, kontakia, etc.

[citation needed] A troparion to the Mother of God (Theotokos) is called a Theotokion (Greek: Θεοτοκίον, Slavonic: Bogoródichen); plural: Theotokia (Θεοτοκία).

[citation needed] A famous example, whose existence is attested as early as the 4th century, is the Vespers hymn, Phos Hilaron, "Gladsome Light"; another, O Monogenes Yios, "Only Begotten Son", ascribed to Justinian I (527 - 565), occurs in the introductory portion of the Divine Liturgy.

Perhaps the earliest set of troparia of known authorship are those of the monk Auxentios (first half of the 5th century), mentioned in his biography but not preserved in any later Byzantine order of service.