The period between sunset and sunrise, especially the hours of darkness. This period considered as a unit of time: for two nights running. This period considered from its conditions: a rainy night. The period between dusk and midnight of a given day: either late Thursday night or early Friday morning. The period between evening and bedtime. This period considered from its activities: a night at the opera. This period set aside for a specific purpose: Parents' Night at school. The period between bedtime and morning: spent the night at a motel. One's sleep during this period: had a restless night. Nightfall: worked from morning to night. Darkness: vanished into the night. A time or condition of gloom, obscurity, ignorance, or despair: "In a real dark night of the soul it is always three o'clock in the morning\u201d ( F. Scott Fitzgerald). A time or condition marked by absence of moral or ethical values: "He never would have let us go untroubled into the night of private greed\u201d ( Anthony Lewis). Of or relating to the night: the night air. Intended for use at night: a night light. Working during the night: the night nurse. Active chiefly at night: night prowlers. Occurring after dark: night baseball.