auditor

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. One that audits accounts.
2. n. One who audits a course.
3. n. One who hears; a listener.

Century Dictionary and Cyclopedia

1. n. A hearer; one who listens to what is said; a member of an auditory.
2. n. Same as audient, n.
3. n. A person appointed and authorized to examine an account or accounts, compare the charges with the vouchers, examine parties and witnesses, allow or reject charges, and state the result. It is usual with courts to refer accounts involved in litigation to auditors, in some jurisdictions called referees or commissioners, for adjustment, and their report, if received, is the basis of the judgment. Sometimes an auditor is a standing officer of political or corporate bodies. State or municipal auditors are persons appointed or elected to examine the public accounts as they accrue, or at such intervals as may be designated. In the United States government there are six auditors of the treasury. The first auditor has charge of the accounts of the civil service, customs, judiciary, public debt, etc.; the second, those of Indian affairs and some of those of the army; the third, those of the quartermaster-general, engineer corps, commissary-general, war claims, etc.; the fourth, those of the navy; the fifth, those of the internal-revenue office, census, patent-office, and state department; and the sixth, those of the post-office department.
4. n. One of certain officers of high rank at the papal court: so called from their connection with business treated of in audiences with the pope: as, auditor of the apostolic chamber; auditor of the pope; auditors of the Roman rota (which see).

Wiktionary

1. n. One who audits bookkeeping accounts.
2. n. In many jurisdictions, an elected or appointed public official in charge of the public accounts; a comptroller.
3. n. One who audits an academic course; who attends the lectures but does not earn academic credit.
4. n. rare One who listens as a member of an audience
5. n. Scientology One trained to perform spiritual guidance procedures.

GNU Webster's 1913

1. n. A hearer or listener.
2. n. A person appointed and authorized to audit or examine an account or accounts, compare the charges with the vouchers, examine the parties and witnesses, allow or reject charges, and state the balance.
3. n. One who hears judicially, as in an audience court.

WordNet 3.0

1. n. a student who attends a course but does not take it for credit
2. n. a qualified accountant who inspects the accounting records and practices of a business or other organization
3. n. someone who listens attentively