the Berasit Hebrew Dictionary

'Yeber' (aka Eber), is a character from Genesis who was Abraham's great-great-great-great-grandfather.

Genesis 10:21 appears to imply that Yeber might be another name for Sem. Specifically, the verse seems to refer to Sem as “the father of all the children of Yeber.” If Sem is the father, but the children are the children of Yeber, then presumably both Yeber and Sem are the father. Or perhaps, one of them is the mother? Thus, Yeber might be a woman, and therefore the matriarch of Abraham and his decsendants.

The heyeberi (Hebrews) take their name from Yeber.