'Thousands' in the Bible

Then Solomon spoke to all Israel, to the commanders of thousands and of hundreds, to the judges, and to every leader in all Israel—the heads of the families.

These are their numbers according to their ancestral families. For Judah, the commanders of thousands:Adnah the commander and 300,000 brave warriors with him;

Then Amaziah gathered Judah and assembled them according to ancestral house, according to commanders of thousands, and according to commanders of hundreds. He numbered those 20 years old or more for all Judah and Benjamin. He found there to be 300,000 choice men who could serve in the army, bearing spear and shield.