aphesis

In phonetics and phonology, apheresis (/əˈfɛrɪsɪs, əˈfɪərɪsɪs/; British English: aphaeresis) is the loss of one or more sounds from the beginning of a word, especially the loss of an unstressed vowel, thus producing a new form called an aphetism (/ˈæfɪtɪzəm/). https://en.wikipedia.org/wiki/Apheresis_(linguistics)