PCS

*ˁVŝb- - grass (Fronzaroli 1968: 274, 289, 299; Kogan 2011: 200; Kogan 2015: 183)

The only possible trace of this root outside CS can be found in Akk. ešēbu ‘to grow luxuriantly’. Its relationship to the Akkadian plant name išbabtu is considerably less certain because of the peculiar morphological shape of the Akkadian word.
Sab. ˁs₃bt ‘pastureland’ and Qat. ˁs₃b ‘crops, produce’, often compared to this root (Fronzaroli 1968:289), can hardly be related in view of the phonological irregularity (ESA s₃ does not normally correspond to PS ŝ) (Kagan 2015: 183)

Hebrew
ˁēŝäb - grass, herb (HALOT 889)
Syriac
ˁesbā - grass (LSyr. 536, SL 1118)
Arabic
ˁušb- - herbage, fresh herbs (Lane 2050)
Tigre
ˁešbay - a plant with tendrils (WTS 466)
seems to be an Arabism