'Thousands' in the Bible

and ten princes with him, one prince, one prince, for a house of a father, for all the tribes of Israel, and each of them a head of a house of their fathers, for the thousands of Israel.

And the sons of Reuben, and the sons of Gad, and the half of the tribe of Manasseh, answer and speak with the heads of the thousands of Israel:

And Phinehas the priest, and the princes of the company, and the heads of the thousands of Israel, who are with him, hear the words which the sons of Reuben, and the sons of Gad, and the sons of Manasseh have spoken, and it is good in their eyes.