Dunya
Etymology
The triliteral root dāl nūn wāw (د ن و) occurs in the Quran 133 times.
1. Compare with English «down» - "from a high to a low position, downwards, "
2. Compare with English «here below»
This world and in the Hereafter
(2:130) Who would abandon the creed of Abraham except one who fools himself? We have selected him in this world (Arab. الدُّنْيَا, l-dun'yā), and in the Hereafter, he is of the reformers.
(3:45) The Angels said, "O Mary, God gives good news of a word from Him. His name is the Messiah, Jesus the son of Mary. Honorable in this world (Arab. الدُّنْيَا, l-dun'yā) and in the Hereafter, and from among those who are made close."
The lower heaven
(67:5) We have adorned the lower (Arab. الدُّنْيَا, l-dun'yā) heaven with lamps, and We made it with projectiles against the devils; and We prepared for them the retribution of the blazing fire.