[1] : The Collaborative International Dictionary of English v.0.48

abacus \ab"acus\ a^b".aku^s, n.; e. pl. abacuses; l.
   pl. abaci -simac. l. abacus, abax, gr. 'a`bax
   1. a table or tray strewn with sand, anciently used for
      drawing, calculating, etc. obs.
      1913 webster

   2. 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.
      1913 webster

   3. arch.
      a the uppermost member or division of the capital of a
          column, immediately under the architrave. see
          column.
      b a tablet, panel, or compartment in ornamented or
          mosaic work.
          1913 webster

   4. a board, tray, or table, divided into perforated
      compartments, for holding cups, bottles, or the like; a
      kind of cupboard, buffet, or sideboard.
      1913 webster

   abacus harmonicus mus., an ancient diagram showing the
      structure and disposition of the keys of an instrument.
      --crabb.
      1913 webster
see also:
abacuses abaci column abacus harmonicus 

[2] : WordNet (r) 2.0

abacus
     n 1: a tablet placed horizontally on top of the capital of a
          column as an aid in supporting the architrave
     2: a calculator that performs arithmetic functions by manually
        sliding counters on rods or in grooves
     also: abaci pl
see also:
abaci 

[3] : WordNet (r) 2.0

abaci
     see abacus
see also:
abacus 

Abaci >> A Words
Abaci, definition of term: Abaci
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