Etymology PIE word *dwóh₁ From Middle English twilight, twyelyghte, equivalent to twi- (“double, half-”) + light, literally ‘second light, half-light’. Cognate to Scots twa licht, twylicht, twielicht (“twilight”), Low German twilecht, twelecht (“twilight”), Dutch tweelicht (“twilight, dusk”), German Zwielicht (“twilight, dusk”). Compare Old English twēone lēoht (“twilight”).
1
The soft light in the sky seen before the rising and (especially) after the setting of the sun, occasioned by the illumination of the earth’s atmosphere by the direct rays of the sun and their reflection on the earth.
Near-synonym: half-light
I could just make out her face in the twilight.
2
The time when said light is visible; the period between daylight and darkness.
It was twilight by the time I got back home.
At twilight in the summer there is never anybody to fear—man, woman, or cat—in the chambers and at that hour the mice come out. They do not eat parchment or foolscap or red tape, but they eat the luncheon crumbs.1892, Walter Besant, chapter II, in The Ivory Gate […], New York, N.Y.: Harper & Brothers, […], →OCLC:
3
Any faint light through which something is seen.
Two women, Eusabio’s wife and sister, looked on from the deep twilight of the hut.1927, Willa Cather, Death Comes for the Archbishop, Book VII, section 4, page 233:
4
Astronomy, Natural sciences The time when the sun is less than 18° below the horizon.
5
Broadly, Figuratively An in-between or fading condition through which something is perceived.
The twilight of one's life
, Book IV, Chapter XIV The twilight […] of probability.
1 more example
“They have not enough heart,” said Edith, with a smile. The very twilight of a smile: so singularly were its light and darkness blended.1846 October 1 – 1848 April 1, Charles Dickens, Dombey and Son, London: Bradbury and Evans, […], published 1848, →OCLC:
Etymology PIE word *dwóh₁ From Middle English twilight, twyelyghte, equivalent to twi- (“double, half-”) + light, literally ‘second light, half-light’. Cognate to Scots twa licht, twylicht, twielicht (“twilight”), Low German twilecht, twelecht (“twilight”), Dutch tweelicht (“twilight, dusk”), German Zwielicht (“twilight, dusk”). Compare Old English twēone lēoht (“twilight”).
1
Pertaining to or resembling twilight; faintly illuminated; obscure.
2
Synonym of mesopelagic (“Describing the pelagic zone of the ocean between the photic epipelagic and the aphotic bathypelagic zones, characterized by very minimal light.”)
Etymology PIE word *dwóh₁ From Middle English twilight, twyelyghte, equivalent to twi- (“double, half-”) + light, literally ‘second light, half-light’. Cognate to Scots twa licht, twylicht, twielicht (“twilight”), Low German twilecht, twelecht (“twilight”), Dutch tweelicht (“twilight, dusk”), German Zwielicht (“twilight, dusk”). Compare Old English twēone lēoht (“twilight”).