imperceptible : (adj.) atisukhuma; indriyāgocara.

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

bltar med pa

[translation-san] {C} adṛśya

[translation-eng] {C} imperceptible

Jeffrey Hopkins' Tibetan-Sanskrit-English Dictionary

mthong ba med pa

[translation-san] {C} apaśyaka

[translation-eng] {Hopkins} not seen; not perceived

[translation-eng] {C} imperceptible; not to be seen

Jeffrey Hopkins' Tibetan-Sanskrit-English Dictionary