n. pl. ba·ses (-sēz′)
1. A fact or circumstance on which something is established: rumors with no basis in reality. See Synonyms at base1.
2. The chief constituent; the fundamental ingredient: The basis for most liquids is water.
3. The fundamental principle: Objective inquiry is the basis of science.
a. A pattern or schedule for proceeding: on a weekly basis.
b. A condition for relating or proceeding: a first-name basis; a friendly basis.
5. Archaic A physical base on which something rests.
[Middle English, foundation upon which something rests, base, from Latin, from Greek, a stepping, that on which one stands, base; see gwā- in the Appendix of Indo-European roots.]
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