Adjustable head rest for a seat, especially for an automotive vehicle seat

The invention relates to a headrest (1) adjustable in orientation, intended to be fixed to the backrest of a seat, in particular a seat for a motor vehicle, comprising a U-shaped arm (3) each of whose branches (31, 32) is adapted to be introduced into a housing formed in the seat, and padding (4) adapted to pivot around the base of the arm. According to the invention, it comprises a housing (2) around which the padding is disposed, said housing (2) comprising a hollowed upper part (21) in which are formed at least two grooves (230) adapted to house the base (33) of the arm (3) and, in which is inserted at least one spring blade (5) adapted to hold the base of the pivoting arm in a groove.