obi sash
A decorative sash worn over the obi, often visible above the obi when wearing kimono. Part of traditional Japanese attire.
When wearing a kimono, you let the obi sash peek out above the obi.
Compound of 帯 (obi, 'sash') and 揚げ (age, 'raising' or 'lifting'), referring to the sash that is raised or visible above the obi.