Abaci

n. frame holding bars strung with beads which are used to make mathematical calculations; uppermost part of a column (Architecture)

An abacus (plurals abacuses or abaci), also called a counting frame, is a calculating tool for performing arithmetical processes, often constructed as a wooden frame with beads sliding on wires. The user, called an abacist, slides counters by hand on rods or in grooves. It was in use centuries before the adoption of the written Hindu-Arabic numeral system and is still widely used by merchants and clerks in China, Japan, Africa and elsewhere.
See more at Wikipedia.org...

Noun
1. a tablet placed horizontally on top of the capital of a column as an aid in supporting the architrave
(hypernym) tablet
2. a calculator that performs arithmetic functions by manually sliding counters on rods or in grooves
(hypernym) calculator, calculating machine

n. maker or seller of croase wool cloth or garments

(pl. )
of Abacus