adj. 25B6; adjective
an arbitrary decision : CAPRICIOUS, whimsical, random, chance, unpredictable; casual, wanton, unmotivated, motiveless, unreasoned, unsupported, irrational, illogical, groundless, unjustified.
the arbitrary power of a prince : AUTOCRATIC, dictatorial, autarchic, undemocratic, despotic, tyrannical, authoritarian; absolute, uncontrolled, unlimited, unrestrained.
reasoned, democratic.