emblema

The central panel of a mosaic pavement, usually rendered in fine technique and representing a figural scene. Emblemata (pl.) were prepared separately in the mosaic workshop and inserted into larger pavements of less complicated design.

Emblema (Roger Urlich)

Emblema with the head of Medusa.  From Pompeii, the House of the Vestals (VI, 1,7). Early 1st c. CE. Museo Archeologico Nazionale di Napoli. Photo:  Dr. Roger Ulrich.