One among the thousand names of Viṣṇu (Vishnu). It is not possible for ordinary people to comprehend or realise within themselves the true nature of God, be it through their physical being or rigorous meditation and penance. God is not perceptible (grāhya) by means of sensual experiences. Thus He is agrāhya or imperceptible —karmendriyairna gṛhyate iti agrāhyaḥ.
About this incomprehensible (agrāhya) brahma Tayittirīya Upaniṣada says that neither can the heart or its whispers reach Him, nor can it perceive Him; therefore, the heart returns home from its quest, defeated— yato vāco nivartante aprāpya manasā saha.