1. The outlet of body through which the soul-units (jīva-pradeśas) depart from the body at the time of death.
maraṇakāle śaririṇaḥ śarīrānnirgamastasya mārgo niryāṇamārgaḥ.
(Sthā 5.214 Vṛ Pa 328)
2. Path to liberation (emancipation of soul)-
The spiritual path through which the soul attains the Nirvāṇa (final emancipation).
niryāṇamārgaḥ viśiṣṭanirvāṇaprāptikāraṇamityarthaḥ.
(Āva 4.9 HāVṛ p. 181)