Heb. deber, “destruction,” a “great mortality”, the fifth plague that fell upon the Egyptians (Ex. 9:3). It was some distemper that resulted in the sudden and widespread death of the cattle. It was confined to the cattle of the Egyptians that were in the field (9:6).
Easton’s Bible Dictionary
Murrain
Easton’s Bible Dictionary, M. G. Easton (1897). Public domain, from the CrossWire SWORD module.