A type of Kriyā (urge);
the activity of throwing any object (animate or inanimate), which becomes the cause of the bondage of Karma.
nisarjanaṃ nisṛṣṭaṃ, kṣepanamityarthaḥ, tatra bhavā tadeva vā naisṛṣṭikī, nisṛjato yaḥ karmabandhaḥ.
(Sthā 2.26 Vṛ Pa 39)