pre ‧ de ‧ ter ‧ min ‧ er /ˌpriːdɪˈtɜːmənə, ˌpriːdɪˈtɜːmɪnə $ -ˈtɜːrmənər/ BrE AmE noun [countable]
technical a word that is used before a ↑ determiner (=a word such as ‘the’, ‘that’, ‘his’ etc) . In the phrases ‘all the boys’ and ‘both his parents’, the words ‘all’ and ‘both’ are predeterminers.