dyad
/ˈdaɪæd/noun
1- technical something that consists of two elements or parts〈技〉二, 一双, 一对：
the mother-child dyad.
母子二人组合。
1.1
- Mathematics an operator which is a combination of two vectors【数】并矢, 并向量。
派生词
dyadic
adjective词源
late 17th cent. (originally denoting the number two or a pair)： from late Latin dyas, dyad-, from Greek duas, from duo 'two'. Current senses date from the late 19th cent.