Ashtangasamgraha 28.7

28.7

tadvayaḥsthāpanāddoṣasthāpanādvāsthāpanamityucyate śarīrārohaṇāddoṣanirharaṇādacintyaprabhāvatayā yasminnūhāsambhavānnirūha iti ||

It is called āsthāpana because it stabilizes youth (vayaḥsthāpana) or stabilizes the doṣas (doṣasthāpana); it is called an evacuating enema (nirūha) because it ascends into the body, removes doṣas, and because—due to its inconceivable potency—it is that in which no conjecture (ūhā) is possible.