front thong of a sandal or clog
Refers specifically to the front strap (鼻緒) of traditional Japanese footwear such as 草履 or 下駄, where the thong passes between the big toe and second toe.
The front thong of my zori sandal broke.
I replaced the front thong of my geta clogs with a new one.
Compound of 前 (front) and 鼻緒 (thong of a sandal). The derivation is transparent from its components.