A feminine suffix appearing in several names, as suggested by Carl Hostetter and Patrick Wynn (AAD/11). On SD/427, Tolkien said that the affix -th was often found in feminine forms.
-êthsuffix. feminine suffix
-îsuffix. feminine suffix
A suffix used to form feminine nouns from common or masculine nouns (SD/435). Another common variant was -ê (SD/438).