Etymologically, the exercise of authority signifies « to increase», « to enlarge».
Someone with authority increases the capacity for action or the knowledge of those affected by it, e.g., an author increases our store of inherited knowledge by his writing.
Neither authoritarianism nor power, authority expresses itself principally in the domains of education and leadership.
The word AUTHORITY comes from the latin verb ‘augere’ which means « to increase», « to enlarge», « to develop ». In each case, authority or the person exercising it inspires imagination, creativity which leads to growth.
We find this meaning in the following expressions:
He is an authority (he is an expert); he is authoritative (he inspires respect); moral authorities or higher authorities (groups or institutions which aspire to be revered).
(source: Précis de Sociologie”, Jean-Michel Morin)