The light perceived before the rising, and after the setting, of the sun, or when the sun is less than 18° below the horizon, occasioned by the illumination of the earth's atmosphere by the direct rays of the sun and their reflection on the earth.
Imperfectly illuminated; shaded; obscure.
the interval of time preceding sunrise and following sunset (see sunrise, sunset) during which the sky is partially illuminated. Civil twilight comprises the interval when the zenith distance, referred to the centre of the Earth, of the central point of the Sun's disk is between 90° 50¢ and 96° , nautical twilight comprises the interval from 96° to 102° , astronomical twilight comprises the interval from 102° to 108° .
the time of day immediately following sunset; "he loved the twilight"; "they finished before the fall of night"
the diffused light from the sky when the sun is below the horizon but its rays are refracted by the atmosphere of the earth
lighted by or as if by twilight; "The dusky night rides down the sky/And ushers in the morn"-Henry Fielding; "the twilight glow of the sky"; "a boat on a twilit river"
The period of decreasing sky brightness after sunset, or of increasing sky brightness before sunrise. There are three definitions of twilight: Civil Twilight, Nautical Twilight, and Astronomical Twilight. Twilight lasts longer in higher latitudes.
The intervals of incomplete darkness following sunset and preceding sunrise. There are several kinds of twilight: civil twilight, nautical twilight, and astronomical twilight are in common usage.
An intermediate period of illumination of the sky before sunrise and after sunset; there are three definitions of twilight: civil, nautical, and astronomical.
Often called dusk, it is the evening period of waning light from the time of sunset to dark. The time of increasing light in the morning is called dawn. Twilight ends in the evening or begins in the morning at a specific time and can be categorized into three areas of decreasing light. Civil twilight is the time in the evening when car headlights need to be turned on to be seen by other drivers. Nautical twilight is when the bright stars used by navigators have appeared and the horizon may still be seen. Astronomical twilight is when the sunlight is still shining on the higher levels of the atmosphere, yet it is dark enough for astronomical work to begin. During dawn, the reverse order occurs until full daylight.
The time at the beginning of the day immediately before sunrise and at the end of the day after sunset when the sky remains illuminated.
Twilight is the time before sunrise or after sunset when sunlight scattered in the upper atmosphere illuminates the lower atmosphere and the surface of the Earth.