(1) Attorney means any person who is a member in good standing of the bar of the highest court of any state, territory, or possession of the United States, including a Commonwealth, or the District of Columbia.

(2) Certified public accountant means any person who is duly qualified to practice as a certified public accountant in any state, territory, or possession of the United States, including a Commonwealth, or the District of Columbia.

(3) Commissioner refers to the Commissioner of Internal Revenue.

(4) Practice before the Internal Revenue Service comprehends all matters connected with a presentation to the Internal Revenue Service or any of its officers or employees relating to a taxpayer's rights, privileges, or liabilities under laws or regulations administered by the Internal Revenue Service. Such presentations include, but are not limited to, preparing documents; filing documents; corresponding and communicating with the Internal Revenue Service; rendering written advice with respect to any entity, transaction, plan or arrangement, or other plan or arrangement having a potential for tax avoidance or evasion; and representing a client at conferences, hearings, and meetings.

(5) Practitioner means any individual described in paragraphs (a), (b), (c), (d), (e), or (f) of § 10.3.

(6) A tax return includes an amended tax return and a claim for refund.

(7) Service means the Internal Revenue Service.

(8) Tax return preparer means any individual within the meaning of section 7701(a)(36) and 26 CFR 301.7701-15.