خَفِيَّةٌ

A well: (S, K:) or a deep well; because its water is not perceived, or not apparent: (TA:) or a well of ancient times, that has become filled up and then dug again: (JK, TA:) or any well that has been dug and then left until it has become filled up, then dug again, and cleared out: (ISk, S:) [opposed to بَدِىْءٌ:] according to A'Obeyd, it is so called because it is made to appear: (S:) plural خَفَايَا and خَفِيَّاتٌ. (JK, TA)

And A tangled, or luxuriant, or dense, thicket, (JK, K, TA,) which the lion takes as his covert: (JK, TA:) or خَفِيَّة is the name of a certain place frequented by lions; (S, IB;) and is properly imperfectly decl., so that you say أُسُودُ خَفِيَّةَ; but it may be perfectly decl. in poetry. (IB.)

Also A slight taint, or infection, or a touch, or stroke, of insanity: so in the phrase بِهِ خَفِيَّةٌ In him is a slight taint, &c., of insanity. (Ibn-Menádhir, S, K. *)