n. 系词, 介体, 接合部

[医] 介体; (舌)联桁; 交配

[ noun ]
an equating verb (such as `be' or `become') that links the subject with the complement of a sentence
<noun.communication>

Copula \Cop"u*la\, n. [L., bond, band. See {Couple}.]
1. (Logic & Gram.) The word which unites the subject and
predicate.

2. (Mus.) The stop which connects the manuals, or the manuals
with the pedals; -- called also {coupler}.