thus i read recently a review of a book by sir gavin de beer , and , in what appeared to be a citation from the original , i noted the following opinion on the river-name arar ( livy ) and araros ( polybius ) : 'now arar derives from the celtic root meaning running water which occurs also in many english river-names like avon/ it is a strange world in which avon and araros can have the same 'root ' ( a vegetable analogy still much loved by the non-philological when being wise about words ) .