Modifier (i.e. dependent)
This usage is found, for example, in Fries (1952:202ff.) and Hawkins (1983). It is becoming obsolete.
the adverb very is a modifier of the adjective ill in he is very ill.
- Fries, CC. 1952. The Structure of English. New York: Harcourt, Brace & World.
- Hawkins, John A. 1983. Word order universals. New York: Academic Press.