United States Court of Appeals
                              For the Eighth Circuit
                          ___________________________

                                  No. 17-3154
                          ___________________________

                           Thompson Truck & Trailer, Inc.

                          lllllllllllllllllllllPlaintiff - Appellant

                                             v.

                               United States of America

                         lllllllllllllllllllllDefendant - Appellee
                                        ____________

                      Appeal from United States District Court
                  for the Northern District of Iowa - Cedar Rapids
                                   ____________

                               Submitted: June 12, 2018
                                Filed: August 23, 2018
                                    ____________

Before WOLLMAN, ARNOLD, and STRAS, Circuit Judges.
                         ____________

WOLLMAN, Circuit Judge.

     Thompson Truck & Trailer, Inc. (Thompson), appeals the dismissal of its
complaint, arguing that the district court1 erred in interpreting 26 U.S.C. § 4051(a)(1).
We affirm.

      1
        The Honorable Linda R. Reade, United States District Judge for the Northern
District of Iowa.
        Thompson is a semitruck dealership, whose principal offices are located in
Cedar Rapids, Iowa. Thompson sells trucks equipped with diesel particulate filters
(filters). The filters collect particulate matter from a truck’s exhaust and turn it into
a less harmful substance. Each filter increases a truck’s retail sales price by
approximately $8,000. Under Internal Revenue Code § 4051(a)(1), Thompson must
pay a twelve percent excise tax on the trucks it sells. From April 1, 2011, to
September 30, 2011, Thompson paid the excise tax on the full retail sales price of each
truck sold, which included tax on the $8,000 value of each filter. On July 30, 2014,
Thompson sought a refund of $387,840 from the Internal Revenue Service, arguing
that—based on its interpretation of a federal regulation—the filters should not have
been taxed. The Internal Revenue Service denied Thompson’s claim.

      We review “de novo the grant of a motion to dismiss, taking all facts alleged in
the complaint as true.” Owen v. Gen. Motors Corp., 

, 918 (8th Cir.
2008). We also review de novo the district court’s interpretation of a statute. In re
Racing Servs., Inc., 

, 502 (8th Cir. 2015).

       Thompson argues that the district court erred in its application of Chevron,
U.S.A., Inc. v. Natural Resources Defense Council, Inc., 

(1984). When
conducting a Chevron-based review of an agency’s construction of a statute, we
consider two questions: (1) “whether Congress has ‘directly addressed the precise
question at issue,’” and (2) if Congress has not directly addressed the question at
issue, whether the agency’s rule is “arbitrary or capricious in substance, or manifestly
contrary to the statute.” Mayo Found. for Med. Educ. & Research v. United States,

, 52-53 (2011) (quoting 

; Household Credit
Servs., Inc. v. Pfennig, 

, 242 (2004)).

      Thompson argues that the district court erred at step one of the Chevron
analysis by concluding that under 26 U.S.C. § 4051(a)(1) Congress had directly
addressed the precise question at issue—whether the filters qualified as a “part or
accessory.” The text of § 4051 states:

                                          -2-
      (a) Imposition of tax.—
            (1) In general.—There is hereby imposed on the first retail sale of the
                  following articles (including in each case parts or accessories sold
                  on or in connection therewith or with the sale thereof) a tax of 12
                  percent of the amount for which the article is so sold:
                  (A) Automobile truck chassis.
                  (B) Automobile truck bodies.
                  (C) Truck trailer and semitrailer chassis.
                  (D) Truck trailer and semitrailer bodies.
                  (E) Tractors of the kind chiefly used for highway transportation
                         in combination with a trailer or semitrailer.2

Thompson claims that the phrase “parts or accessories” is ambiguous. We disagree.
As we have stated previously, “[w]hen a word is not defined by statute,” as is the case
here, “we normally construe it in accord with its ordinary or natural meaning.” United
States v. Jungers, 

, 1071 (8th Cir. 2013) (quoting Smith v. United
States, 

, 228 (1993)). “Ordinarily, a word’s usage accords with its
dictionary definition.” Yates v. United States, 

, 1082 (2015). “If the
words convey a definite meaning, which involves no absurdity, nor any contradiction
of other parts of the instrument, then that meaning, apparent on the face of the
instrument, must be accepted . . . .” United States v. I.L., 

, 821 (8th Cir.
2010) (quoting Lake Cty. v. Rollins, 

, 670-71 (1889)).


      2
        The origins of the statute date back to the War Revenue Act of 1917, Pub. L.
No. 65-50 § 600(a), 40 Stat. 300, 316, which imposed an excise tax on the sale of “all
automobiles, automobile trucks, automobile wagons, and motorcycles, sold by the
manufacturer, producer, or importer.” Congress subsequently passed the Revenue Act
of 1918, Pub. L. No. 65-254, § 900(1)-(3), 40 Stat. 1057, 1122, which introduced the
phrase “parts and accessories” by taxing automobile trucks, automobile wagons, other
automobiles, motorcycles, and items sold with them “including tires, inner tubes,
parts, and accessories.” After several repeals and reenactments, Congress passed the
Highway Revenue Act of 1982, Pub. L. No. 97-424, § 512, 96 Stat. 2168, 2174-75,
which created the current statute.


                                          -3-
       We conclude that when the phrase “parts or accessories” is given its ordinary
or natural meaning, the statute is not ambiguous and the filters fall within its scope.
 A “part” is “[a]ny of the manufactured objects that go to make up a machine or
instrument, now esp. a motor vehicle; a component.”3 And an “accessory” is “[a]
subordinate or auxiliary thing; an adjunct; an accompaniment; (now) esp. a minor
fitting or attachment.”4 Applying these definitions, we conclude that the filters are
parts or accessories of the trucks sold by Thompson because they are components of
the trucks or minor fittings or attachments included with the trucks. This
interpretation of § 4051(a)(1) is consistent with the provisions of the Internal Revenue
Code as a whole. For example, § 4053 exempts specific items from taxation such as
camper coach bodies for self-propelled mobile homes; feed, seed, and fertilizer
equipment; house trailers; ambulances and hearses; concrete mixers; trash containers;
mobile machinery; and idling reduction devices. 26 U.S.C. § 4053. Congress
possesses the authority to exempt the filters under § 4053, but has chosen not to
include such an exemption. Because the plain meaning of the words “parts or
accessories” involves no absurdity or contradiction when considered in light of the
code as a whole, the section must be given its ordinary or natural meaning.

       Thompson argues that such an interpretation of “parts or accessories” is
inconsistent with Mayo, in which the Supreme Court held that the term “student” was
ambiguous under the Federal Insurance Contributions Act when applied to medical
residents who took classes and worked full 

. Mayo is
distinguishable, however, because it involved dueling classifications—whether

      3
        Part,   n.I.8,   Oxford      English      Dictionary   Online,
http://www.oed.com/view/Entry/138188?result=1&rskey=mY2H5h& (last visited
July 30, 2018).
      4
        Accessory, n.A.2.a, Oxford English Dictionary Online,
http://www.oed.com/view/Entry/1046?redirectedFrom=accessory#eid (last visited
July 30, 2018).

                                          -4-
medical residents should be considered students or employees, with students being
exempt from the tax. No similar ambiguity exists here, because there is only one
reasonable interpretation in this case: the filters are either parts or accessories, both
of which the statute subjects to tax. Cf. id.; Mayo Found. for Med. Educ. & Research
v. United States, 

, 680 (8th Cir. 2009), aff’d, 

.

    Given our decision under step one of the Chevron analysis, we do not consider
Thompson’s arguments regarding the federal regulations.

      The judgment is affirmed.
                      ______________________________




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