from
The Collaborative International Dictionary of English v.0.48
Abacus \Ab"a*cus\ ([a^]b"[.a]*k[u^]s), n.; E. pl. {Abacuses}; L.
pl. {Abaci} (-s[imac]). [L. abacus, abax, Gr. 'a`bax]
1. A table or tray strewn with sand, anciently used for
drawing, calculating, etc. [Obs.]
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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.
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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.
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4. A board, tray, or table, divided into perforated
compartments, for holding cups, bottles, or the like; a
kind of cupboard, buffet, or sideboard.
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{Abacus harmonicus} (Mus.), an ancient diagram showing the
structure and disposition of the keys of an instrument.
--Crabb.
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