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Synonyms

abacus

American  
[ab-uh-kuhs, uh-bak-uhs] / ˈæb ə kəs, əˈbæk əs /

noun

plural

abacuses, abaci
  1. a device for making arithmetic calculations, consisting of a frame set with rods on which balls or beads are moved.

  2. Architecture. a slab forming the top of the capital of a column.


abacus British  
/ ˈæbəkəs /

noun

  1. a counting device that consists of a frame holding rods on which a specific number of beads are free to move. Each rod designates a given denomination, such as units, tens, hundreds, etc, in the decimal system, and each bead represents a digit or a specific number of digits

  2. architect the flat upper part of the capital of a column

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of abacus

1350–1400; Middle English < Latin: board, counting board, re-formed < Greek ábax

Explanation

An abacus is an ancient tool used for calculating that remains popular in some places even today. Some sort of counter (beads, beans, stones) is moved in a groove or on a wire to represent the different numbers in the equation. Abacus is a Latin word from a Greek word abax, which meant "counting table." The original abaci were created in sand. The plural abacuses can also be used. In architecture, an abacus can also refer to a flat slab that sits on top of the broad part of a pillar or column (called the capital) to help support a beam (called an architrave) that rests across several pillars.

Keep Reading on Vocabulary.com

Vocabulary lists containing abacus

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Calculators, cars and probably candles and the abacus were considered a menace to society.

From The Wall Street Journal • Dec. 7, 2025

Recently, a lovely and well-meaning friend texted me one of those trending articles that make you want to trade your smartphone for an abacus and never speak of the internet again.

From New York Times • Mar. 9, 2024

For example, you can add numbers perfectly using an abacus, in which wooden beads are pushed back and forth to represent arithmetic operations.

From Science Daily • Oct. 30, 2023

Ms Truss, a former Treasury minister, accused her old department of promoting an "abacus economics" and insisted there needed to be a greater focus on stimulating economic growth.

From BBC • Jul. 20, 2023

They are tools that exist as notations on the page and in my mind; like the abacus, they transform the way I operate on numbers.

From "The Invention of Science" by David Wootton