to wind (of a road, river, etc.); to meander; to twist; to snake
to undulate; to surge; to swell; to roll; to billow
山道がくねくねとうねっている。
The mountain road winds and twists.
大蛇のようにうねる川を見下ろす。
I look down at the river snaking like a serpent.
山道は谷に沿って大きくうねった。
The mountain road wound sharply along the valley.