noun
abacus
A flat slab forming the top of a column's capital.
The abacus formed a flat square above the column's capital.
Etymology
Greek abax named a board or flat slab. The architectural use applies that image directly to the flat upper member of a capital, which supports what rests above the column.
More examples
- A cracked abacus supported the architrave.
- The sculptor carved the underside of the abacus.
- Each column ended in a broad stone abacus.
Forms
abacus · abacuses · abaci
Similar words
- capital
- The capital is the top part of a column; the abacus is its upper slab.
- architrave
- An architrave rests above columns; the abacus caps the capital supporting it.