است

المحيط في اللغة للصاحب بن عباد
است

اِسْتٌ, signifying The podex, or the anus, (K,) or signifying the former, and sometimes used as meaning the latter, (S in art. سته,) is with a conjunctive hemzeh, [written اسْتٌ, when not immediately preceded by a quiescence,] and its final radical letter is clided; for the original form is سَتَهٌ; (Msb;) and it is mentioned in art. سته. (K.) [It is of the fem. gender.] It is said in a prov., applied to him who fails of attaining the object that he seeks, أَخْطَأَتِ اسْتُهُ الحُفْرَةَ [His anus missed the hole in the ground]. (Meyd.)

[Hence,] اِسْتُ الدَّهْرِ (tropical:) The first, or beginning, of time; (A;) old, or ancient, time. (IB, A, * K. *) One says, مَا زَالَ عَلَى اسْتِ الدَّهْرِ مَجْنُونًا (tropical:) [He ceased not, or has not ceased, from the beginning of time, or from old time, to be insane, or mad; or] he always was, or always has been, known as being insane, or mad: like as one says, عَلَى إِسِّ الدَّهْرِ. (Az, S.) And Aboo-Nukheyleh says, مَا زَالَ مُذْ كَانَ عَلَى ا سْتِ الدَّهْرِ ذَا حُمُقٍ يَنْمِى وَعَقْلٍ يَحْرشى (tropical:) [He ceased not, or has not ceased, to be, since he was in the beginning of time, or in old time, i. e., from the first of his existence, a person of increasing foolishness, and of decreasing intellect]. (Az, S.) IB says, J has erred in mentioning است in this section [of the S]; its proper place being in art. سته, where he has also mentioned it; for its hemzeh is conjunctive, by common consent; and if conjunctive, it is augmentative: also, his saying that they have changed the [final]

س in إِسٌّ into ت, like as they have changed the [final] س of طَسٌّ into ت, making this word طَسْتٌ, is a mistake; for, were it so, the hemzeh of است would be disjunctive [in every case; whereas it is always conjunctive except after a pause, when it is pronounced with kesr]: moreover, he has attributed this assertion to Az, who never made it, but only mentioned است الدهر with اسّ الدهر because of their agreement in meaning. (TA.) b2: [Hence also,] اِسْتُ الكَلْبَةِ (assumed tropical:) Calamity, or misfortune: (K:) adversity; difficulty; distress; affliction: (TA:) what is hated, disliked, disapproved, foul, abominable, or evil. (K.) b3: and اِسْتُ المَتْنِ (assumed tropical:) The desert: (K:) or the wide desert. (TA.) b4: See also art. سته.

أُسْتِىٌّ The warp of cloth; (K;) as also أُسْدِىٌّ and أُزْدِىٌّ: (TA:) but it is improperly mentioned in this art.; for it is [originally أُسْتُوىٌ,] of the measure أُفْعُولٌ. (K.) اِسْتِىٌّ Of, or relating to, the اِسْت. (TA in art. سته.)