Upasthāpanā (Upasthapana) in Jainism means re-initiation as an expiation. It is one of the nine basic prāyaścittas (purifications) described in the Jain scriptures, and it refers to re-admitting or re-initiating a monk who has been expelled or who has committed a serious fault, back into the monastic order after proper penance. In short: it is the act of rejoining the order after fault and penance, as a form of purifying the wrong done. There are slight variations in naming and emphasis between Digambar and Śvetāmbara texts, but the core idea remains reform, repentance, and re-entry into the spiritual path. You can read more here