In phonetics and phonology, apheresis (/əˈfɛrɪsɪs, əˈfɪərɪsɪs/; British English: aphaeresis) is a sound change in which a word-initial vowel is lost, e.g., American > 'Merican.
[1] The more specific term aphesis (and its adjective aphetic) is sometimes used to refer to the loss of unstressed vowels.
In historical phonetics and phonology, the term "apheresis" is often limited to the loss of an unstressed vowel.
It typically supplies the input enabling acceptance of apheresized forms historically, such as especially > specially.
The result may be doublets, such as especially and specially, or the pre-apheresis form may fail to survive (Old French eschars > English scarce).