poss : possessive modifier

A possessive modifier (poss) is either a possessive pronoun or a noun phrase containing a possessive marker that modifies the head of a noun phrase.

The possessive pronoun "his" modifying "book".

The possessive modifier including the possessive marker "'s".

The possessive modifier including the possessive marker "'".

The possessive pronoun "my" modifying "son", which includes the possessive marker "'s" and modifies "dad".