Akkadian

ušummu - dormouse

Var. šummu (known from later texts only). According to Englund 1995 45 ff. u. is to be identified with the bandicoot rat rather than dormouse as previously thought.

PS
*ŝVm- - kind of mouse, rat (SED II No. 214)
Not very reliable since ŠU in the Eblaite form points to ṯ rather than *ŝ or *š in the protoform which is not compatible with š in Arb.