hranitelj

1. breadwinner; provider
   Posle očeve smrti on je postao hranitelj porodice. — After his father's death he became the family's breadwinner.
2. (of a family) foster parent
   Dečak živi kod hranitelja već tri godine. — The boy has been living with foster parents for three years.
   Postali su hranitelji dvoje dece. — They became foster parents to two children.

The feminine form is "hraniteljka"; "hraniteljska porodica" means foster family. A legal guardian is "staratelj".