يأس1 يَئِسَ, (S, M, A, Msb, K,) مِنَ الشَّىْءِ, (S, A *, Msb,) aor. ـْ and يَيْئِسُ, (S, M, Msb, K,) the latter of which is extr., (Sb, S, M, K,) like يَحْسِبُ, aor.  of حَسِبَ, and يَنْعِمُ, aor.  of نَعِمَ, (As, S, TA,) and is of the dial. of the higher classes of Mudar, as are also the similar instances, but the former is of the dial. of the lower classes of the Mudar; (Az, S, Msb, TA;) or, as Sb says, accord. to his companions, the verb was originally of two forms, يَئِسَ, aor. ـْ and يَأَسَ, aor. ـْ and a compound [which is يَئِسَ having يَيْئِسُ for its aor. ] was  then formed from the two; but as to وَمِقَ, aor. ـِ and وَفِقَ, aor. ـِ and وَرِمَ. aor. ـِ and وَلِىَ, aor. ـِ and وَثِقَ, aor. ـِ and وَرِثَ, aor. ـِ in each of these only one form is allowable, with the kesr; (S, TA;) and some change the second ى of the aor.  of يَئِسَ into ا, and say يَايَسُ and يَآءَسُ; (Mbr, S, TA;) and I'Ab reads, in the Kur. xii. 87, يِيئَسُ, after the manner of the dial. of those who pronounce the first letter of the aor.  with kesr excepting such as is with ى [for its first letter], (K, TA,) which dial, is that of Temeem and Keys and Hudheyl and Asad; (Ks, Lh, TA;) the case of ى being made an exception by them because kesr with that letter is difficult of pronunciation; (Sb, TA;) but some of the Benoo-Kelb pronounce ى also with kesr, which is extr.; (Fr, Lb, TA:) and this is done in the instances of يِيئَسُ and يِيجَلُ because one ى is here strengthened by another; (K, TA;) [I find also, in a copy of the M, يَئِيسُ, as an extr. form of the aor.  of this verb, on the authority of Sb; but it is doubtless a mistranscription for يِيئَسُ; and there is another evident mistranscription in a quotation from Sb immediately following in that copy, relating to aor. . of the form of يِيئَسُ, which has been rendered correctly above, in the present work, from the TA;] inf. n. يَأْسٌ (S, M, A, Msb, K) and يَأَسٌ, (TA,) or يَآسٌ, (as in a copy of the M,) and يَآسَةٌ; (Ibn-'Abbád, M, K, TA [but in a MS. copy of the K I find it written يَأَسَةٌ; and in the CK, يَأْسَة;]) and إِيَاسٌ is also used as an inf. n. of this verb, though properly an inf. n. of 4; (Msb;) He despaired of the thing; syn. of the inf. n. قُنُوط, (S, A, K,) contr. of رَجَآءٌ: (M, A, K:) or he cut off hope of the thing: (A, K: *) or his hope of the thing became cut off: (Mgh:) and ↓ إِسْتَيْئَسَ signifies the same, (S, A, K,) in like manner followed by مَنْ; (S;) and so does ↓ إِتَّأَسَ, (S, K,) [originally إِيتَأَسَ,] of the measure إِفْتَعَلَ, but with incorporation [of the ى into the ت]. (S.) It is allowable to transpose the letters of يَئِسَ, so as to say أَيِسَ; but not those of the inf. n. (Msb.) There is not a word in the Arabic language commencing with ى followed by ء except يَئِسَ [and its derivatives] (IKtt) [and يَأَيَأَ and its derivatives, and words commencing with an augmentative ى followed by a radical يَاُ^َ]. The expression لَا يَأْسَ مِنْ طُولٍ.occurring in a description of Mohammad, means that his stature was such as would not make [one] to despair of his height; for he was nearer to tallness than he was to shortness: (K, * TA:) يأس is here an indeterminate noun governed in the accus. case by the negative لا: (TA:) or, accord. to one relation, the words are, لَا يَائِسَ مِنْ طُولٍ, [in the CK, erroneously, لا يايَسُ,] meaning, that his height was not despaired of; i. e., he who vied with him in tallness would not despair of him on account of his excessive height: (K, TA:) so that يَائِس is here in the sense of مَيْؤُوس, like مَآءٌ دَافِقٌ in the sense of مَدْفُوقٌ. (TA.) b2:  [Hence,] يَئِسَتْ المَرْأَهُ The woman was, or became, barren. (Msb.) b3: يَئِسَ, (S, M, A, Msb, K,) aor. ـْ and يَيْئِسُ, (M,) also signifies (tropical:)  He knew; syn. عَلِمَ; (S, M, A, Msb, K;) in the dial. of En-Nakha'; (S, Msb;) or, accord. to El-Kelbee, (M,) or Ibn-El-Kelbee, (TA,) in the dial. of Wahbeel, a tribe of En-Nakha'; or, accord. to El-Kásim  Ibn-Maan, of the dial. of Hawázin. (M, TA.) So in the Kur. [xiii. 30] أَفَلَمْ يَيْئَسِ الَّذِينَ آمَنُوا [Do not then those who have believed know?]: (S, M, Msb, K:) or, accord. to some of the lexicologists, do not then those who have believed know with a knowledge wherewith they despair of its being otherwise than what they know? or the meaning is, do not then those who have believed despair of the belief of those whom God has described as those who will not believe? (M, TA;) but I' Ab (M, TA) and 'Alee and others (TA) used to read أَفَلَمْ يَتَبَيَّنِ الَّذِينَ آمَنُوا; and I'Ab said that he thought that the writer had written يَيْئَس in a state of drowsiness. (M *, TA.) Soheym Ibn-Wetheel El-Yarboo'ee also  uses the verb in this sense, in a verse cited in art. يسر, voce يَسَرَ, q. v. (S, M *). [Z-says,] Yousay, قَدْ يَئِسْتُ أَنَّكَ رَجُلُ صِدْقٍ, meaning, (tropical:)  I have known [that thou art a good man], because with eager desire is restlessness, and with the cessation thereof is quiet and tranquility; wherefore it is said, اليَأْسُ أَحَدُ الرَّاحَتَيْنِ [Despair is one of the two states of rest.] (A, TA.) 4 أَيْأَسَهُ, (S, M, A, Mgh, K,) inf. n. إِيَاسٌ, (L, Mgh, Msb,) of the same measure as كِتَابٌ, (Msb,) originally إِيْآسٌ, (L, Msb,) like إِيْعَاسٌ, (L,) and إِيْمَانٌ, (Msb,) He made him to despair: (S, M, A, K:) or to cut off hope: (A:) or to cease to have hope: (Mgh:) مَنْ كَذَا of such a thing: (S:) as also ↓ آيَسَهُ [from أَيِسَ]. (Mgh, K.) b2:  [Hence,] أَيْأُسَهَا اللّٰهُ God made her to be, or become, barren. (Msb.) 8 إِيْتَاَ^َ see 1.10 إِسْتَيْاَ^َ see 1.يَأَسٌ Phthisis, or consumption; syn. سِلٌّ; (M, K;) because he who is affected by it is despaired of; (M;) or [because] the first who was affected by it was اليَأَسُ, (K, TA,) or إِلْيَاس, (TA,) the son of Mudar the son of Nizár: (K, TA:) or, as Suh says, in the R, this disease was called دَآءُ يَاس, or دَآءُ إِلْيَاسَ, because الياس the son of Mudar died of it. (TA.) يَؤُسٌ: see يَائِسٌ.يَؤُوسٌ: see يَائِسٌ.يَئِيسٌ: see يَائِسٌ.يَائِسٌ (M, Mgh, Msb) and ↓ يَئِيس (M) and ↓ يَؤُوسٌ (S, M, A, K) and ↓ يَؤُسٌ (M, K) Despairing: (S, M, A, Mgh, K:) but the third has an intensive signification, (Bd, xli. 49,) [and so the last.]يَائِسَةٌ, A barren woman. (Msb.) مَيْؤُوسٌ مِنْهُ Despaired of. (M, Mgh, Msb. *)