Hebrew

ḳyṣ - to wake up (HALOT 1098)

a byform of yḳṣ

PCS
*yḳṯ̣ - to wake (Kogan 2015: 531)
Contra AHw. 28 and HALOT 431, there is probably no relationship between this root and Akk. akāṣu ‘hartnäckig sein’, akṣu ‘dangerous, overbearing, terrible’