B1noun
شَفَقٌ
shafaq
twilight / afterglow
Example
فَلَا أُقْسِمُ بِالشَّفَقِ
falā uqsimu bish-shafaq
So I swear by the twilight glow (84:16)
Grammar
Masculine noun. Refers to the red/orange glow after sunset. The Quran uses celestial phenomena in divine oaths.
Culture
The Quran's oaths by natural phenomena (dawn, twilight, night, stars) invite contemplation of God's creation as signs.