*arbitrary*

a. [ L. arbitrarius, fr. arbiter: cf. F. arbitraire. See Arbiter. ] 1. Depending on will or discretion; not governed by any fixed rules; as, an arbitrary decision; an arbitrary punishment. [ 1913 Webster ]

It was wholly arbitrary in them to do so. Jer. Taylor. [ 1913 Webster ]

Rank pretends to fix the value of every one, and is the most arbitrary of all things. Landor. [ 1913 Webster ]

2. Exercised according to one's own will or caprice, and therefore conveying a notion of a tendency to abuse the possession of power. [ 1913 Webster ]

Arbitrary power is most easily established on the ruins of liberty abused licentiousness. Washington. [ 1913 Webster ]

3. Despotic; absolute in power; bound by no law; harsh and unforbearing; tyrannical; as, an arbitrary prince or government. Dryden. [ 1913 Webster ]

Arbitrary constant,
Arbitrary function (Math.), a quantity of function that is introduced into the solution of a problem, and to which any value or form may at will be given, so that the solution may be made to meet special requirements. --
Arbitrary quantity (Math.), one to which any value can be assigned at pleasure. [ 1913 Webster ]