Akkadian

rapāšu - to be wide, broad (CAD R 153; AHw. 955)

No transparent WS cognates, but metathesis from *prŝ ‘to spread,’ well attested in Hbr. prŝ (HALOT 975) and Arb. frš (Lane 2369), but conspicuously missing from Akkadian, is perhaps a suitable solution (P. Jensen apud LSyr. 600).