auditor

kuunteluoppilas

kuulija, kuuntelija

tilintarkastaja One who audits bookkeeping accounts.
In many jurisdictions, an elected or appointed public official in charge of the public accounts; a comptroller.
One who audits an academic course; who attends the lectures but does not earn academic credit.
puhekieltä One who listens, typically as a member of an audience.
Sir Thomas Browne

There is another of better notice, and whispered through the world with some attention; credulous and vulgar auditors readily believing it, and more judicious and distinctive heads not altogether rejecting it.