Source : Webster's Revised Unabridged Dictionary (1913)

Axiom \Ax"i*om\, n. [L. axioma, Gr. ? that which is thought
   worthy, that which is assumed, a basis of demonstration, a
   principle, fr. ? to think worthy, fr. ? worthy, weighing as
   much as; cf. ? to lead, drive, also to weigh so much: cf F.
   axiome. See {Agent}, a.]
   1. (Logic & Math.) A self-evident and necessary truth, or a
      proposition whose truth is so evident as first sight that
      no reasoning or demonstration can make it plainer; a
      proposition which it is necessary to take for granted; as,
      ``The whole is greater than a part;'' ``A thing can not,
      at the same time, be and not be.''

   2. An established principle in some art or science, which,
      though not a necessary truth, is universally received; as,
      the axioms of political economy.

   Syn: {Axiom}, {Maxim}, {Aphorism}, {Adage}.

   Usage: An axiom is a self-evident truth which is taken for
          granted as the basis of reasoning. A maxim is a
          guiding principle sanctioned by experience, and
          relating especially to the practical concerns of life.
          An aphorism is a short sentence pithily expressing
          some valuable and general truth or sentiment. An adage
          is a saying of long-established authority and of
          universal application.

Source : WordNet®

axiom
     n 1: a saying that widely accepted on its own merits [syn: {maxim}]
     2: (logic) a proposition that is not susceptible of proof or
        disproof; its truth is assumed to be self-evident

Source : Free On-Line Dictionary of Computing

AXIOM
     
         A commercially available subset of {Scratchpad},
        from {IBM}.
     
        ["Axiom - The Scientific Computing System", R. Jenks et al,
        Springer 1992].
     
        (1995-02-21)

axiom
     
         A {well-formed formula} which is taken to be true
        without proof in the construction of a {theory}.
     
        Compare: {lemma}.
     
        (1995-03-31)

AXIOM*
     
         A {symbolic mathematics} system.
     
        {A#} is one component of AXIOM*.
     
        Version: 2.
     
        (1995-02-21)