Meaning of “authority” - Learner’s Dictionary

authority

noun uk us /ɔːˈθɒrəti/
POWER [ U ]

B2 the official power to make decisions or to control other people:

a position of authority
[ + to do sth ] The investigators have the authority to examine all the company's records.
We need the support of someone in authority.
OFFICIAL GROUP [ C ]
QUALITY [ U ]

the quality of being confident and being able to control people:

She has an air of authority.
an authority on sth

someone who has a lot of knowledge about a particular subject:

She is an authority on seventeenth-century English literature.
→ See also local authority

(Definition of “authority” from the Cambridge Learner’s Dictionary © Cambridge University Press)