קַלּוּת, (קַל II) lightness, swiftness. Tanḥ. Vayḥi 16; Yalk. Gen. 161 קַלּוּתוֹ של איל the swiftness of the hart; a. e.—ק׳ ראש (or sub. ראש) light-mindedness, irreverence, disregard of custom. Keth. 8ᵇ ונהג ק׳ בעצמו וכ׳ and set the example of disregard of custom through himself (inaugurated simplicity at burial), when (according to his request) they buried him in linen garments; M. Kat. 27ᵇ ק׳ ראש; Tosef. Nidd. IX, 17 הנהיג … ק׳ ר׳ וכ׳. Succ. 51ᵇ והיו באים לידי ק׳ ר׳ and they were led into irreverence (through the presence of women); Tosef. ib. IV, 1. Ab. III, 13 שחוק וק׳ ר׳ מרגילין וכ׳ laughter and frivolity make man familiar with unchastity. Tanḥ. Miḳḳ. 9 שלא ינהוג ק׳ ר׳ בגבורה lest man become irreverent towards the Almighty.