When I was preparing my recent article about the Little Vespers of the Byzantine Office, I had a chat with one of the wise men I consult about such things, and we got to talking about the length of the service known as All-night Vigil. As previously noted, the term “all” in “All-night” is something of a rhetorical exaggeration, but in large monasteries such as the great houses on Mt Athos, not by much, and this was his description of the order of services for a patronal feast which he attended at one of them.
“Ninth Hour, Small Vespers, dinner in the refectory with solemn procession from the church and then back afterwards.
Break for confessions
Beginning of All-Night Vigil proper
– Vespers with Artoklasia (4 hours; the troparia at the
artoklasia took 30 minutes with the
terirems, Psalm 103 took 1.5 hours)
Reading of the Saint’s Life (around midnight)
Orthros
After the Kontakion of the Sixth Ode they passed to a full Akathistos (I went to sleep at that point) (Presumably) First, Third, and Sixth Hours, Divine Liturgy
Then procession with water blessing.
Lunch”
Me: “Terirems?” (This word struck me not only because I had never heard it before, but also because it doesn’t sound Greek at all.)
The wise man explained to me that terirems are nonsense syllables added to the liturgy, which were originally spontaneous expressions of joy added to the texts when sung. Over time, they came to be completely scripted, and it is considered part of Byzantine musical formation to study the codified ones. Not at all surprisingly, theological pseudo-explanations have been created to explain them, e.g., that they are words that the angels sing in heaven, or of a lullaby which the Virgin Mary sang to Christ. There is very little information about them available on the internet, but some of the very few references I was able to find say that they were also used to cover the gaps in the music if the clergy hadn’t finished what they were doing. (The syllables te-, ri-, -rem are not the names of notes, by the way.)
Here are a few of examples. You can find more on YouTube by searching in various languages; in Greek, the word is τεριρεμ, in Slavonic and its derivatives, терирем.