impersonal verb

Wiktionary

1. n. linguistics A verb used only in the infinitive or in the third-person. In the third person, the subject is either implied or a dummy.

GNU Webster's 1913

1. adj. (Gram.) a verb used with an indeterminate subject, commonly, in English, with the impersonal pronoun it; as, it rains; it snows; methinks (it seems to me). Many verbs which are not strictly impersonal are often used impersonally; as, it goes well with him.