Arbitration, Arbitrary

Does an arbitrator in an arbitration process make arbitrary decisions? Hmmm…
 
Arbitration
 
The words arbitrary and arbitration have unknown origins. The earliest known source is Latin arbiter (one who goes somewhere as a witness or a judge; he who hears and decides a case; a judge, umpire, mediator).1
 
The English word arbitress appears in the mid-14th century meaning a woman who settled disputes. The word arbiter or arbitrator (a person who has power of judging absolutely according to his own pleasure in a dispute or issue) came to English in the late 14th century. The use of arbiter to mean one chosen by two disputing parties to decide the matter is from the 1540s.
 
The word arbitration meaning the faculty of making a choice or decision, judgment, discretion is from the late 14th century. Arbitration meaning the authority or responsibility for deciding a dispute is from the early 15th century. Arbitration meaning the settlement of a dispute by a third party is from the 1630s.
 
Arbitrary
 
In contrast to the word arbitration, the word arbitrary has taken on somewhat negative connotations. The adjective arbitrary meaning deciding by one’s own discretion or depending on one’s judgment is from the early 15th century. By the 1640s, the meaning of arbitrary had gradually come to mean capricious, ungoverned by reason or rule, or despotic. Today, the word arbitrary is defined by Merriam-Webster as “not planned or chosen for a particular reason; not based on reason or evidence; done without concern for what is fair or right.”
 
1 One suggestion is that the word arbiter comes from the name of Gaius Petronius Arbiter (~27 – 66 CE), a friend of the Emperor Nero and the reputed author of the Satyricon, a book with a rather raunchy if not decadent reputation. Maybe the fact that his name and the word arbiter are the same is just a coincidence.
 
Reference: Online Etymological Dictionary, https://www.etymonline.com/
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