The Cambridge Grammar of the English Language (Page 329) has a section titled 'Nominals':
Intermediate between the noun and the NP we recognise a category of nominals:
 a. the old man
b. that book you were talking about
CGEL defines phrases like old man and book you were talking about as nominals. That is, nominals are defined as an NP minus any determiner.
Is there a corresponding term in traditional grammar or school grammar?