A sub-type of Nāma (body-making) Karma, the Udaya (rise) of which is responsible for the establishment of the mutual relation between the Karma-pudgalas (material clusters qua Karma), which have been already appropriated and which are in the process of being appropriated.
yadudayāt karmaṇapudgalānāṃ gṛhītānāṃ gṛhyamanānām ca parasparaṃ sambandhastatkārmanabandhananāma.
(Prajñā 23.43 Vṛ Pa 470)