predeterminer

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun An adjectival word that can stand before an article, a possessive pronoun, or another determiner, as all in all the flowers or both in both his children.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun grammar The function of a phrase that precedes a determiner in a noun phrase and modifies the head noun.