アバクスMeanings1nounabacus (architecture)architectureTechnical term in architecture for the flat slab on top of a column capital. Not the calculating device (that is そろばん).from Greekドーリア式しきの柱ちゅう頭とうの上うえにあるアバクスは、シンプルな正せい方ほう形けいの板いただ。The abacus on top of a Doric capital is a simple square slab.