copula

名词 copula:

1. an equating verb (such as `be' or `become') that links the subject with the complement of a sentence
   同义词：copulative, linking verb

cop.u.la

n.（名词）
Grammar A verb, such as a form ofbe or seem, that identifies the predicate of a sentence with the subject. Also called linking verb
【语法】 系词：将一个句子的谓语和主语连起来的动词，如be 或 seem 的一种形式 也作 linking verb
Logic The word or set of words that serves as a link between the subject and predicate of a proposition.
【逻辑学】 联项：在一个命题的主项和谓项间起联系作用的词或词组

来源：
Latin côpula [link]
拉丁语 côpula [联系]

【引伸】
cop.ular