The antimins (from the Greek , Antimension: "instead of the table"), is a special corporal required to be on the altar in many Eastern Christian liturgical traditions. It was originally used as a portable version of an altar.
It is a rectangular piece of cloth of either linen or silk, typically decorated with representations of the Descent of Christ from the Cross, the Four Evangelists, and inscriptions related to the Passion. A small relic of a martyr is sewn into it. In the Latin Church of the Catholic Church, an altar stone serves a similar function. In the Coptic Church and Syriac Church, it has been replaced by a wooden altar-board or altar-slab.
Syriac practice A wooden tablet, the ţablîtho, is the liturgical equivalent of the antimins in the churches of Syriac tradition.
See also Tabot Corporal (liturgy) Antependium Sthathicon
References
Further reading Antimensium article in the Catholic Encyclopedia Coptic Antimensium article in the Claremont Coptic Encyclopedia