And the night when it 'asa'sa (عسعس)

Meaning: when its darkness departs, or when it approaches. Both interpretations are narrated from Ibn Abbas and others. According to al-Mubarrad, it is one of the addad (words with opposite meanings).

Al-Raghib stated: 'as'asa and 'asas refer to the thinness or dimness of darkness, and this occurs at both ends of the night. Thus, according to him, it is a word of shared meaning (mushtarak ma'nawi) rather than a word of opposite meanings. He interpreted 'asa'sa here as both approaching and departing, stating that this applies to the beginning of the night and its end.

Al-Farra' said: The commentators have reached a consensus that the meaning of 'asa'sa is "it departed." Al-'Ajaj supports this, describing wine or the desert: "Until the morning breathed for it, and its night turned away and departed ('asa'sa)."

It is also said that this is specifically the dialect of the Quraysh. Others have said that its meaning as "its darkness approached" is more appropriate for the statement of the Exalted...