Difference between Unreasonable and Arbitrary

UNREASONABLE vs ARBITRARY: ADJECTIVE

Based on or subject to individual discretion or preference or sometimes impulse or caprice
Based on or subject to individual judgment or preference.
Relating to a decision made by a court or legislature that lacks a grounding in law or fact.
Not limited by law; despotic.
Depending on will or discretion; not governed by any fixed rules
Exercised according to one's own will or caprice, and therefore conveying a notion of a tendency to abuse the possession of power.
Despotic; absolute in power; bound by no law; harsh and unforbearing; tyrannical.
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.
One to which any value can be assigned at pleasure.
Based on individual discretion or judgment; not based on any objective distinction, perhaps even made at random.
Determined by impulse rather than reason; heavy-handed.
Any and all possible.
Determined by independent arbiter.
Determined by chance, whim, or impulse, and not by necessity, reason, or principle.

Not showing good judgment
Synonyms Absurd, Silly, Foolish, etc. (see absurd), obstinate, wrong-headed, extravagant, unfair, unjust, extortionate.
Inconvenient.
Not listening to or acting according to reason; not guided by reason; not influenced by reason.
Not reasonable or agreeable to reason; irrational.
Exceeding the bounds of reason; beyond what is reasonable or moderate; exorbitant; immoderate: as, an unreasonable price.
Not endowed with reason; irrational.

Not regulated by fixed rule or law; determinable as occasion arises; subject to individual will or judgment; discretionary.
Ungoverned by reason; hence, capricious; uncertain; unreasonable; varying; changeful: as, an arbitrary character.
Not characterized by or manifesting any overruling principle; fixed, determined, or performed at will; independent of rule or control.
Uncontrolled by law; using or abusing unlimited power; despotic; tyrannical.
In law, properly determinable by the choice or pleasure of a tribunal, as distinguished from that which should be determined according to settled rules or the relative rights or equities of the parties.

Senseless, Incongruous, Silly, Indefensible, Inordinate, Undue, Foolish, Untenable, Excessive, Absurd, Irrational, Illogical, Unrealistic, Unjustified, Unwarranted

Perverse, Subjective, Indiscriminate, Unfair, Unwarranted, Unjustifiable, Unjust, Unjustified, Unreasonable, Absolute, Whimsical, Discretionary, Impulsive, Discretional, Capricious

Senseless, Incongruous, Silly, Indefensible, Inordinate, Undue, Foolish, Untenable, Excessive, Absurd, Irrational, Illogical, Unrealistic, Unjustified, Unwarranted

Perverse, Subjective, Indiscriminate, Unfair, Unwarranted, Unjustifiable, Unjust, Unjustified, Unreasonable, Absolute, Whimsical, Discretionary, Impulsive, Discretional, Capricious

Disarm unreasonable and difficult behavior when correctly used.
Therefore all progress depends on the unreasonable man.
An attorney shall not make an agreement for, charge, or collect an unreasonable fee or an unreasonable amount for expenses.
It would, for example be unreasonable to insist on compliance with the clause if it was unreasonable or impossible for the person to comply.
Whether a behaviour is unreasonable can depend on whether a reasonable person might see the behaviour as unreasonable in the circumstances.
Charter arguments, such as unreasonable delay, the right to be secure against unreasonable search and seizure, and the right to counsel.
You can definitely sue for unreasonable delays if you can prove that the delays are, in fact, unreasonable.
The traveller complained that the arrest was unreasonable and that various actions of the involved police officers were unreasonable.
An unreasonable comprehensive doctrine is unreasonable in the sense that it is incompatible with the duty of civility.
The Right Against Unreasonable Search and Seizure The Fourth Amendment protects persons from unreasonable searches and seizures.

But some guests consider the refund conditions arbitrary.
Tribe contends, its action was arbitrary and capricious.
Allows data frames to contain an arbitrary number of bits and allows character codes with an arbitrary number of bits per character.
Third, any legislation will require this committee or any other to draw arbitrary lines, but some arbitrary lines are better or worse than others.
Instead it encompasses the right to benefit from freedoms such as arbitrary destruction, arbitrary interference and the freedom to choose where to live.
While the formula is arbitrary it relates to economic reality, and any allocation is arbitrary in the absence of comparables.
It need not separate them in the arbitrary way I have, or invoke them in my arbitrary order.
Working Group on Arbitrary Detention ruled that his detention was arbitrary and violated international law.
Assume that the new box is a cavity with arbitrary shape, whose walls have an arbitrary emissivity.
Arbitrary items Two arbitrary parameters can be registered.