The Japanese word for night is
夜

よる - yoru

Japanese Definition

夜
1. n. the night, evening
東京の夜 - Tokyo nights
夜の街を歩く - literally to walk the night streets
不安な夜を過ごす - literally to pass an uneasy night
夜の星空を見上げる - to look up at the night's starry skys starry sky
2. n. (literary) night, evening
『真夏の夜の夢』 - A Midsummer Night’s Dream

日暮れ
1. n. sunset, sundown, dusk, evening, nightfall

闇
1. Usage: Added to the jōyō kanji list on 30 November 2010; previously classified as jinmeiyō kanji.
2. n. the dark, darkness
3. n. darkness, the dark
4. n. a dark place
5. n. (Buddhism) darkness, as a metaphor for worldly desires