noun \ˈa-bə-kəs, ə-ˈba-\

: a device used for counting and calculating by sliding small balls or beads along rods or in grooves

plural aba·ci \ˈa-bə-ˌsī, -ˌkē; ə-ˈba-ˌkī\ or aba·cus·es

Full Definition of ABACUS

:  an instrument for performing calculations by sliding counters along rods or in grooves
:  a slab that forms the uppermost member or division of the capital of a column

Illustration of ABACUS

Origin of ABACUS

Latin, from Greek abak-, abax, literally, slab
First Known Use: 14th century

Other Mathematics and Statistics Terms

abscissa, denominator, divisor, equilateral, exponent, hypotenuse, logarithm, oblique, radii, rhomb


noun    (Concise Encyclopedia)

Calculating instrument that uses beads that slide along a series of wires or rods set in a frame to represent the decimal places. Probably of Babylonian origin, it is the ancestor of the modern digital calculator. Used by merchants in the Middle Ages throughout Europe and the Arabic world, it was gradually replaced by arithmetic based on Hindu-Arabic numerals. Though rarely used in Europe past the 18th century, it is still used in the Middle East, China, and Japan.


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