Hebrew

ḳayiṣ - summer; summer fruit; summer harvest (HALOT 1098)

PWS
*ḳayṯ̣-̣ - summer (Kogan 2015: 125)
Shall one tentatively compare Akk. kaṣû ‘to be cold’ – otherwise virtually without Semitic etymology – with an enantiosemic shift of meaning possibly paralleled by Akk. šarāpu ‘to burn’– šurīpu ‘ice’, for which see Eilers 1986:41? Cf. also Gez. ḥamad ‘ashes’ – ḥamadā ‘snow’. On this hypothetical semantic development see also Fronzaroli 1965a:142