قَيْظٌ

The most vehement, or intense, heat of summer; (S, K;) from the [auroral] rising of the Pleiades, [which, at the commencement of the era of the Flight, was about the 13th of May, O. S.,] to the [auroral] rising of Canopus, [which, at the same period, was about the 4th of August, O. S.:] (K:) or vehemence, or intenseness, of heat: (Msb:) plural [of pauc.] أَقْيَاظٌ and [of mult.] قُيُوظٌ. (K.)

Also, The quarter which people [commonly] call the صَيْف; (Msb;) the summerquarter, commencing when the sun enters the sign of Cancer; so termed by some, who called the spring-quarter the صَيْف, and the autumnal-quarter the رَبِيع; others [in later times] calling the summer-quarter the صيْف, the spring-quarter the رَبِيع, and the autumnal-quarter the خَرِيف; but agreeing with the former in calling the winterquarter the شِتَاء: (Mir-át ez-Zemán:) the Arabs say, that the year consists of four seasons, every one of these being three months; namely, the quarter called the صَيْف, which is that called رَبِيعُ الكَلَإِ, consisting of [the Syrian months] Ádhár and Neysán and Eiyár [or March and April and May, O. S.]; then, the quarter called the قَيْظ, consisting of Hazeerán and Temmooz and Áb [or June and July and August, O. S.]; then, the quarter called the خَرِيف, consisting of Eylool and the two Tishreens [or September and October and November, O. S.]; and then, the quarter called the شِتَاء, consisting of the two Kánoons and Shubát [or December and January and February, O. S.]. (Az, TA.)

لَا تَقُومُ السَّاعَةُ حَتَّى يَكُونَ الوَلَدُ غَيْظًا والمَطَرُ قَيْظًا, a saying of Mohammad, meaning [The resurrection, or the time thereof, will not come to pass until the birth of a child be an occasion of wrath, or rage, and] rain be accompanied by air like the قيظ [or most vehement heat of summer]. (TA.)

إِجْتَمَعَ القَيْظُ is an elliptical and abridged phrase, meaning The people, or company of men, assembled themselves in the قَيْظ [or summer]. (TA.)