As used in this chapter, the following terms have the meaning ascribed to them in this section, except when the context clearly indicates otherwise:

(1) COMMISSIONER. The Commissioner of the Department of Revenue.

(2) CONTACT or CONTACTED. Previous contact of any kind by the department or an agent of the department within five years prior to the initial written request for amnesty. This includes returns filed for the tax types included in the application for tax periods beginning before the look-back period. Contact includes, but is not limited to, with regard to potential liability for the type of tax identified in the amnesty application: receipt of a nexus questionnaire, an audit or notice of audit, payment of tax, registration for tax, registration with the Secretary of State, request for extension of time to file, making a payment of estimated tax, filing a return, and non-compliance issued in response to an application for a certificate of good standing or a certificate of compliance by the taxpayer, or on behalf of the taxpayer.

(3) COURIER. A messenger other than the United States Postal Service that delivers parcels, packages, and the like, containing returns, reports, and other documents or payments.

(4) DEPARTMENT. The Department of Revenue.

(5) LOOK-BACK PERIOD. The last three full tax years or 36 months of tax returns which are delinquent.

(6) POSTMARK. An official mark made by the United States Postal Service on a piece of mail to cancel the stamp and to indicate the place and date of sending.

(7) TAX PERIOD. Any period for which a tax return is required by law to be filed with the department.

(8) TAXPAYER. Any individual or entity subject to any tax imposed by any law of the State of Alabama, payable to the State of Alabama, and collected by the department.