from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A manual computing device consisting of a frame holding parallel rods strung with movable counters.
  • noun Architecture A slab on the top of the capital of a column.

from The Century Dictionary.

  • noun A tray strewn with dust or sand, used in ancient times for calculating.
  • noun A contrivance for calculating, consisting of beads or balls strung on wires or rods set in a frame.
  • noun In architecture: The slab or plinth which forms the upper member of the capital of a column or pillar, and upon which rests, in classic styles, the lower surface of the architrave.
  • noun Any rectangular slab or piece; especially, a stone or marble tablet serving as a sideboard, shelf, or credence.
  • noun In Roman antiquity, a board divided into compartments, for use in a game of the nature of draughts, etc.
  • noun The mystic staff carried by the grand master of the Templars.
  • noun The structure and arrangement of the keys or pedals of a musical instrument.

from the GNU version of the Collaborative International Dictionary of English.

  • noun obsolete A table or tray strewn with sand, anciently used for drawing, calculating, etc.
  • noun A calculating table or frame; an instrument for performing arithmetical calculations by balls sliding on wires, or counters in grooves, the lowest line representing units, the second line, tens, etc. It is still employed in China.
  • noun The uppermost member or division of the capital of a column, immediately under the architrave. See Column.
  • noun A tablet, panel, or compartment in ornamented or mosaic work.
  • noun A board, tray, or table, divided into perforated compartments, for holding cups, bottles, or the like; a kind of cupboard, buffet, or sideboard.
  • noun (Mus.) an ancient diagram showing the structure and disposition of the keys of an instrument.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun a tablet placed horizontally on top of the capital of a column as an aid in supporting the architrave
  • noun a calculator that performs arithmetic functions by manually sliding counters on rods or in grooves


from The American Heritage® Dictionary of the English Language, 4th Edition

[Middle English, from Latin, from Greek abax, abak-, counting board, perhaps from a Semitic source akin to Hebrew ’ābāq, dust; see ℵbq in Semitic roots.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Latin abacus, abax; from Greek ἄβαξ ('a`bax, "board covered with sand"), possibly from Hebrew אבק (āvāq, "dust").


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  • More specifically, Buffett's Berkshire Hathaway for its five big bills got an issue of perpetual preferred Goldman shares with a neat 10% annual dividend, which according to our abacus translates into $5 million a year.

    No Magic Potion

  • The columns of these pillared porches have sixteen flutings, a plain abacus, and no plinth.

    Pharaohs, Fellahs and Explorers

  • It now had fence slats and feed bags laid across, and held all types of useful things—shuttlecocks, disposable cameras, Play-Doh molds, and so on—things Joey found discarded, including a functional abacus, which is really quite rare.


  • The Romans also made a mechanical version, with beads sliding in slots, called an abacus.


  • The Romans also made a mechanical version, with beads sliding in slots, called an abacus.


  • The Romans also made a mechanical version, with beads sliding in slots, called an abacus.


  • If you put it down there, where the abacus is the machine's computer would simple take charge of it and offer you lots of nice user-friendly time-travel applications complete with pull-down menus and desk accessories if you like.

    Dirk Gently's Holistic Detective Agency

  • Let the height of the capital be divided into three parts, and give one to the plinth (that is, the abacus), the second to the echinus, and the third to the necking with its congé.

    The Ten Books on Architecture

  • For higher columns the other proportions will be the same, but the length and breadth of the abacus will be the thickness of the lower diameter of a column plus one ninth part thereof; thus, just as the higher the column the less the diminution, so the projection of its capital is proportionately increased and its breadth [2] is correspondingly enlarged.

    The Ten Books on Architecture

  • Thus the fourth column from the west is his, and perhaps the fifth up to the abacus, which is convex and of limestone.

    Bell's Cathedrals: The Cathedral Church of Ripon A Short History of the Church and a Description of Its Fabric


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  • a dusty word written in the sand

    January 9, 2008

  • Generally associated with the Orient but used in Babylon as early as 2400 BC. Also found in ancient Egypt, Greece, and Rome. See Calculating Devices.

    January 27, 2008

  • In castle architecture, "flat portion on top of a capital."

    August 27, 2008

  • Plinth!

    June 1, 2012

  • I yell this as an exclamation.

    March 5, 2018