Pronunciation: (därk'nis),[key] —n. 1. the state or quality of being dark: The room was in total darkness. 2. absence or deficiency of light: the darkness of night. 3. wickedness or evil: Satan, the prince of darkness. 4. obscurity; concealment: The darkness of the metaphor destroyed its effectiveness. 5. lack of knowledge or enlightenment: heathen darkness. 6. lack of sight; blindness.