Lane’s articleإِبْلِيسُ1 sense
1
[A name of Satan]. According to some, it is from أَبْلَسَ in the first of the senses assigned to it above, his former name having been عَزَازِيلُ.
Aboo-Is-hák: it is a foreign word, and for this reason, and because it is also determinate, or a proper name, it is imperfectly declinable.
If it were an Arabic word, it would be perfectly declinable, like إِجْفِيلٌ and إِخْرِيطٌ.
Show Lane's original text
[A name of Satan]; from أَبْلَسَ , (S, M, Msb, K,) in the first of the senses assigned to it above, (S, M, Msb,) accord. to some; (M, Msb, K;) his former name being عَزَازِيلُ : (S, TA:) or it is a foreign word, (Aboo-Is-hák, M, Msb, K,) and for this reason, (Aboo-Is-hák, M, Msb, TA,) and its being also determinate, (Aboo-Is-hák, M, TA,) or a proper name, (Msb,) it is imperfectly decl.; (Aboo-Is-hák, M, &c.;) for if it were an Arabic word, it would be perfectly decl., like إِجْفِيلٌ and إِخْرِيطٌ . (Msb.)