:Degemination:

Pronunciation ˌdiːdʒemɪˈneɪʃn

The change from a geminate (long) sound to the equivalent single (short) sound. An example from Finnish: ˈkirkko “church” (nominative), ˈkirkon (genitive). The process also occurs in English. An example is the pronunciation ˈpraɪ ˈmɪnɪstə instead of ˈpraɪm ˈmɪnɪstə.