twilight-curve

‘twat-lait,ks:zv. [also spelt twilight-cur i the curv or arc, sometimes very sharply defined, censtrtu ing‘the visible part of the circular outline or boundary ¢ the projection of the earth’s shadow upon the sky, whic rises in the east just after the sun has set and, as; pa es to the zenzth and thence to the western horizoi gradually cuts eff the twilight-glow; the twilight-arc.