Surah Al-Fil 105:3

وَأَرْسَلَ عَلَيْهِمْ طَيْرًا أَبَابِيلَ

And He sent against them birds in flocks,

Translation: Saheeh International

Tafsir

and unleashed upon them swarms of birds birds in droves one following the next it is said there is no singular form for it abābīl like asātīr; but some say that the singular is abūl or ibāl or ibbīl similar in constructed pattern to ‘ajūl miftāh and sikkīn

Excerpt from Tafsir al-Jalalayn, commentary on 105:3, via Quran.com. The reader has the full commentary and 9 more tafsirs.