DP-internal semantic agreement: A configurational analysis

"Hybrid" nouns are known for being able to trigger either syntactic or semantic agreement, the latter typically occurring outside the noun's projection. We document and discuss a rare example of a Hebrew noun that triggers either syntactic or semantic agreement within the DP. To explain this and other unusual patterns of nominal agreement, we propose a configurational adaptation of the CONCORD-INDEX distinction, originated in Wechsler and Zlatić (2003). Morphologically-rooted (=CONCORD) features are hosted on the noun stem while semantically-rooted (=INDEX) features are hosted on Num, a higher functional head. Depending on where attributive adjectives attach, they may display either type of agreement. The observed and unobserved patterns of agreement follow from general principles of selection and syntactic locality.