the cardinal number that is the sum of three and one
同义词:four, 4, IV, tetrad, quatern, quaternion, quaternary, quaternity, quartet, foursome, Little Joe
one of four children born at the same time from the same pregnancy
同义词:quad
a set of four similar things considered as a unit
同义词:quartet, quartette, quadruple
quadruplet详细解释
quad.ru.plet n.(名词)One of four offspring born in a single birth.四胞胎之一:一胎出生的四个孩子中的一个A group or combination of four associated by common properties or behavior.四个构成的一组:因共同的财产或行为而联系在一起的四人小组或联盟