It is

来源: 于 2023-12-28 10:41:32 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

from a French verb "fondre", melt by meaning.

Its past participle is fondu,

by adding an "e",

it becomes a feminine name.

Check the word "fondue" in history:

on page 1043 in The Compact Edition of the Oxford English Dictionary.