PES

*sVmbVr - part of the animal's stomach (SED I 233)

May be related with a secondary -m- and a meaning change.

Tigre
səmbər - one of the four stomachs of the ruminants (WTS 173)
Tigrinya
səmbər - parete interna dello stomaco dei ruminanti (inner wall of a ruminant`s stomach) (TED 655, Bassano 1918: 173)
Amharic
sämbär - callosity of the internal wall of the animal's stomach (AED 538–9)
Var. sänbär
Endegen
sämbär - fat part of the stomach (EDG 546)