| | Ācārya | A spiritual master who teaches by his personal example. |
| | Acintya-bhedābheda-tattva | Lord Caitanya's doctrine of the “inconceivable oneness and difference” of God and His creation, establishing the Absolute Truth as both personal and impersonal. |
| | Agni | The demigod controlling fire. |
| | Ahaṁ Brahmāsmī | “I am Brahman.” The spiritual identity of the living entity. |
| | Ahiṃsā | Nonviolence. |
| | Akarma | Krsna conscious activities that carry no reactions, either good or bad. |
| | Ānanda | Transcendental bliss. |
| | Anu | Atomic, minute. |
| | Arcā-vigraha | The incarnation of the Lord in the form of material elements, such as a statue (Deity or mūrti), or painting, or even a mental image. It is manifest to facilitate worship by the devotees in the material world. |
| | Artha | Economic development. |
| | Āsanas | Bodily postures used in yoga discipline. |
| | Ashrama | A spiritual order according to the Vedic social system: brahmacarya (student life), grhastha (householder), vanaprastha (retirement), and sannyasa (renunciation). |
| | Aṣṭāṅga yoga | The eightfold path consisting of yama and niyama (moral practices), asana (bodily postures), pranayama (breath control), pratyahara (sensory withdrawal), dharana (steadying the mind), dhyana (meditation), and samadhi (deep concentration on Visnu within the heart). |
| | Asura | Not godly; demon, or one opposed to God. |
| | Ātma | The self, or soul. |
| | Ātmahan | Killer of the soul; one who neglects spiritual life. |
| | Ātmārāma | Selfsatisfied; one who delights in the Self. |