Definitions for "Linking verb"
A verb that relates the subject complement to the subject. Words commonly used as linking verbs are become, seem, appear, feel, look, taste, smell, sound and forms of the verb be: She is a writer. The bread looks burned.
the verb to he used to join subject to complement: e.g., The apples were ripe.
an equating verb (such as `be' or `become') that links the subject with the complement of a sentence