impair : (v.t.) vikalīkaroti; hāpeti. (v.i.) vikalībhavati; hāyati. (pp.) vikalīkata; hāpita; vikalībhūta; hīna.

A.P. Buddhadatta Mahathera, Concise Pali-English and English-Pali Dictionary [available as digital version from Metta Net, Sri Lanka]

nyams par 'gyur ba

[translation-san] {C} sampramoṣayati (=pramuhyate)

[translation-eng] {Hopkins} become degenerate; deteriorate

[translation-eng] {C} impair

Jeffrey Hopkins' Tibetan-Sanskrit-English Dictionary