'Thousands' in the Bible

Solomon spoke to all Israel, to the captains of thousands and of hundreds, and to the judges, and to every prince in all Israel, the heads of the fathers' [houses].

This was the numbering of them according to their fathers' houses: Of Judah, the captains of thousands: Adnah the captain, and with him mighty men of valor three hundred thousand;

Moreover Amaziah gathered Judah together, and ordered them according to their fathers' houses, under captains of thousands and captains of hundreds, even all Judah and Benjamin: and he numbered them from twenty years old and upward, and found them three hundred thousand chosen men, able to go forth to war, who could handle spear and shield.