authority
noun
ɔːˈθɒrəti 
əˈθɔːrəti əˈθɑːrəti power
1 [uncountable] the power to give orders to peoplein a position of authorityShe now has authority over the people who used to be her bosses.Nothing will be done because no one in authority (= who has a position of power) takes the matter seriously.2 [uncountable] authority (to do something) the power or right to do somethingOnly the manager has the authority to sign cheques.We have the authority to search this building.permission
3 [uncountable] official permission to do somethingIt was done without the principal's authority.We acted under the authority of the UN.organization
4 [countable, usually plural] the people or an organization who have the power to make decisions or who have a particular area of responsibility in a country or regionThe health authorities are investigating the problem.I have to report this to the authorities.the immigration authorities see also local authorityknowledge
5 [uncountable] the power to influence people because they respect your knowledge or official positionHe spoke with authority on the topic.the moral authority to run the countryexpert
6 [countable] authority (on something) a person with special knowledgeSynonym
specialistShe's an authority on criminal law.Idioms
have something on good authority
to be able to believe something because you trust the person who gave you the information
I have it on good authority that he is going to be promoted.