The Emim (Hebrew: אֵמִים) was the Moabite name for one of the tribes of Rephaim. They are described in Deuteronomy chapter 2 as having been a powerful people, populous and having a successful kingdom. They were defeated by the Moabites, who occupied their land. The Emim are also mentioned in Genesis 14:5 and according to Rashi, the name is translated as "the dreaded ones" (Hertz 1936).
"The Emims dwelt therein in times past, a people great, and many, and tall, as the Anakim" (Deuteronomy 2:10-11).
Hertz, J.H. (1936) The Pentateuch and Haftoras. Deuteronomy. Oxford, Oxford University Press.