From The Collaborative International Dictionary of English v.0.48:
Basis \Ba"sis\ (b[=a]"s[i^]s), n.; pl. Bases (b[=a]"s[=e]z).
[L. basis, Gr. ba`sis. See Base, n.]
1. The foundation of anything; that on which a thing rests.
--Dryden.
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2. The pedestal of a column, pillar, or statue. [Obs.]
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If no basis bear my rising name. --Pope.
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3. The groundwork; the first or fundamental principle; that
which supports.
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The basis of public credit is good faith. --A.
Hamilton.
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4. The principal component part of a thing.
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