abaco

Abaco is the Italian form of the Biblical name "Habakkuk". It is also the Italian for abacus in the mathematical and architectural senses.
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n. abacus, frame holding bars strung with beads which are used to make mathematical calculations; (Architecture) uppermost part of a column

n. abacus; uppermost part of a column (Architecture)

n. abacus

= abacus [abacuses/abaci, -pl.].
Ex: The abacus, with its beads strung on parallel wires, led the Arabs to positional numeration and the concept of zero many centuries before the rest of the world.