rāvav רָבַב ‘to multiply’ (Hebrew)

Etymology^?: a primitive root

rāvav v
1) to be or become many, be or become much, be or become great
 1a)(Qal)
  1a1) to be or become many
  1a2) to be or become great
  1a3) to be long (of journey)
2) (Pual) ten thousands