mist; haze: a slight obscuring of the view by fine droplets or particles in the air, usually lighter than fog.
朝のもやで視界が悪かった。
The morning haze made visibility poor.
海の上にもやが立ち込めて船が見えにくい。
A haze had formed over the sea, making the ship hard to see.
街の灯がもやにぼやけて見える夜だった。
It was a night when the city lights looked blurred by the haze.