'Tribe' in the Bible

If a priest’s daughter is married to a layman [one not part of the priestly tribe], she shall not eat the offering of the holy things.

And the Israelitish woman's son blasphemed the name of the LORD, and cursed. And they brought him unto Moses: (and his mother's name was Shelomith, the daughter of Dibri, of the tribe of Dan:)

Set aside and consecrate the fiftieth year to declare liberty throughout the land for all of its inhabitants. It is to be a jubilee for you. Every person is to return to his own land that he has inherited. Likewise, every person is to return to his tribe.

His uncle or his uncle's son may redeem him or any blood relative from his tribe may redeem him. If he becomes rich, then he may redeem himself.