(a) Statutory definitions. All terms used in this part that are defined in section 102 of the National Traffic and Motor Vehicle Safety Act of 1966 (15 U.S.C. 1391) are used as defined in the Act.

(b) Motor Vehicle Safety Standard definitions. Unless otherwise indicated, all terms used in this part that are defined in the Motor Vehicle Safety Standards, part 571, of this subchapter (hereinafter “The Standards”), are used as defined therein without regard to the applicability of a standard in which a definition is contained.

(c) Regroovable tire means a tire, either original tread or retread, designed and constructed with sufficient tread material to permit renewal of the tread pattern or the generation of a new tread pattern in a manner which conforms to this part.

(d) Regrooved tire means a tire, either original tread or retread, on which the tread pattern has been renewed or a new tread has been produced by cutting into the tread of a worn tire to a depth equal to or deeper than the molded original groove depth.