For the purposes of automobile tax, "motor vehicle" means, among the motor vehicles prescribed in Article 2, paragraph (2) of the Road Transport Vehicle Act (Act No. 185 of 1951), standard-sized motor vehicles prescribed in Article 3 of that Act and, among the small-sized motor vehicles prescribed in that Article, those with three or more wheels.
自動車税について、「自動車」とは、道路運送車両法（昭和二十六年法律第百八十五号）第二条第二項に規定する自動車のうち、同法第三条に規定する普通自動車及び同条に規定する小型自動車のうち三輪以上のものをいう。
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motor vehiclemachine translation
「自動車」
A motor vehicle as defined in Article 2, paragraph 2 of the Road Transport Vehicle Act that is an ordinary motor vehicle (普通自動車), or a small motor vehicle (小型自動車) with three or more wheels, as Article 3 of that Act classes them.
Defined inArticle 145, paragraph (1)