Coming of age ceremony (cf Baptism, Barmitzvah etc), for Tarvuist children when they reach the age of 9. This age is symbolic, as it represents the age Tarvu was when he stepped on dry land.
During the Erbuniatum ceremony the children have to recite sacred texts in Tarvish, bake their own cake, known as an 'Erbunty roundling' (made from flour, egg, sugar, aniseed and onion), which is given to the Priestmunty, who must eat it all in front of the congregation without sipping water. If the Priestmunty does need a drink, this means bad luck for the child's family.
The Erbuniatunty (name given to the child who is having the Erbuniatum) must also perform a complicated dance, known as a 'Harri-finty'. The ceremony ends with all the congregation whistling and clapping at the same time (to sound in the child's transition from boy to man/girl to woman), as the Erbuniatunty is carried above them, and passed down through the temple. Finally the Erbuniatunty is put into a sort of cot (called a 'Thessle') and rocked to sleep. (It is customary for the child to feign sleeping).
Above: 19th century illustration of Chuldvintl Dickens (son of Charles Dickens) on the Eve of his Erbunaitum.