As a Noun: 1. The part of each period of twenty-four hours when it is dark outside, especially the time when most people are sleeping. English = night. 2. The time of the day between the end of the afternoon and the time when you go to bed. English = evening. 3. The lack of light in a place. English = dark, darkness. As a Verb or Adjective: 1. To become darker and darker at the end of the afternoon; to become evening; to become night. 2. Of a place or the sky, to become darker, for example because it is nearly night. English = darken. 3. Of a place or situation, to lack light and to be difficult to see in. English = (be) dark.