يَقِنَهُ, (Ṣ, Mṣb, Ḳ,) and يَقِنَ بِهِ; (Mṣb;) andأَيْقَنَهُ↓, (Ṣ, Ḳ,) andايقن↓ بِهِ; (Ḳ;) andتَيَقَّنَهُ↓; andاِسْتَيْقَنَهُ↓, (Ṣ, Mṣb, Ḳ,) andاستيقن↓ بِهِ; (Ḳ;) all signify the same; (Ṣ;) He knew it; he was, or became, certain, or sure, or he made sure, of it; syn. عَلِمَهُ; (Mṣb, Ḳ;) intuitively, and inferentially; (Mṣb;) [see 1 in art. علم;] and تَحَقَقَّهُ. (Ḳ.)

يَقِينٌ is of the measure فَعِيلٌ in the sense of the measure فَاعِلٌ, signifying Sure, or certain, and manifest. (Mṣb.)

And knowledge, or certainty; [see ظَنٌّ;] instinctive and inferential. (Mṣb.)

عَيْنُ اليَقِينِ: see عَيْنٌ (latter part).

الحقُّ اليَقِينُ and حَقُّ اليَقِينِ: see جَامِعٌ; where the two words are said to have the same meaning: and Bḍ and Jel in lvi. 95; in the latter of which, اليقين in حَقُّ اليَقِينِ is expressly said to be an epithet: see also Ḥam, p. 335.