Tessellatum — meaning 'Tessellated' - is a term frequently employed in the context of opus tessellatum, distinguishing it from wall mosaics and opus sectile.

Opus tessellatum refers specifically to floor mosaics created by arranging small, uniform tesserae in a tessellated pattern. This technique was extensively used in ancient Roman and Byzantine art to create intricate geometric designs and pictorial scenes. The meticulous arrangement of tesserae in opus tessellatum exemplifies the skill and precision of mosaic artisans, resulting in visually stunning and enduring works of art.