Areal reconstruction

*ŝarr- - king (Kogan 2015:92)

Notable, the opposition *ŝarr- vs. *malik- as a feature of the East/West Semitic dichotomy.

Akkadian
šarru - king (CAD Š₁ 76, AHw. 1118)

The origin of the Akkadian šarru is rather uncertain, as its WS cognates are restricted to Ugr. and Hbr. only (see below).

Ugaritic
šr - prince, sovereign (DUL 842)
Hebrew
ŝar - official, commander (HALOT 1351)