noun
Sea of Japan side; Japan Sea coast
Refers to the regions of Japan along the Sea of Japan, known for heavy snowfall in winter.
日本海側では冬にたくさんの雪が降ります。
On the Sea of Japan side, a lot of snow falls in winter.
Refers to the Pacific Ocean side of Japan, which has a different climate with less snow and more sunshine in winter.
Compound of 日本海 (Sea of Japan) + 側 (side).