【Hearing】 , 【audience】 ,  【audition】  all mean a formal opportunity to be heard by persons having authority to question or the power of decision.

【Hearing】 is not only the general word applicable to such an opportunity not only to be literally heard but to demonstrate worth or qualities in any rational manner, but is also a technical term. In legal use it designates a formal listening by a judge or tribunal to the arguments and proofs offered either in interlocutory proceedings or in a preliminary examination in a criminal case; however, only in equity practice is it applicable to a trial.

It is also used in government and politics for a formal opportunity offered to citizens to state their views on proposed legislation or administrative action, or to present their objections to assessments on property, or to give evidence in a legislative or other investigation.

【Audience】 is more often used of a 【hearing】 that is granted as a favor or mark of esteem than of one that can be demanded as a right; therefore it is used particularly in reference to interviews by appointment granted by a sovereign, a high-ranking ecclesiastic (as a pope), or a diplomatic representative of high standing.

【Audition】 is applicable to a 【hearing】 by expert judges of a performer (as a singer, a musician, a public speaker, an actor, or a dancer) in order to test the merits of his performance with, usually, a view to his possible engagement.