A rolling bearing defines a separation between an oil enclosure and an air enclosure. The bearing includes rolling elements defining a first side opening and a second side opening, and includes an annular junction piece having an annular contact surface with the structural piece. An oil film is disposed at the annular contact surface between the structural piece and the junction piece and is laterally defined by at least two sealing rings. A sealing device covers at least part of the first side opening. A first oil circulation device feeds the oil film with oil and feeds the rolling elements beside the oil enclosure with oil from the oil film. A second oil circulation device, independent of the first, recovers the oil used for lubricating the rolling elements and is arranged in such a manner as to avoid oil flowing towards the air enclosure.