PlutoBrE/ˈpluːtəʊ/NAmE/ˈpluːtoʊ/nounoneofanumberofroundobjectsinspacethatarenotaslargeasplanetsbutwhichgoaroundthesun. InAugust2006, theInternationalAstronomicalUniondeclaredthatPlutoshouldbecalledadwarf planet because it is smaller and has different characteristics from the other planets in our solar system; in 2008 it declared that dwarf planetsfurtherfromthesunthanNeptunecouldalsobecalledplutoids.冥王星(比行星小但围绕太阳旋转的星体之一。2006 年 8 月,国际天文学联合会宣布应将其称为矮行星,因为它比我们太阳系的其他行星小,而且有着不同的特点。2008 年,国际天文学联合会宣布较海王星离太阳更远的矮行星也可称为类冥矮行星。)