One of the major names of Śiva (Shiva) featuring in the Aṣtottara Sahasranāma (Ashtottara Sahasranama) verse [an incantation recounting one thousand and eight names of Śiva] is Atri. Elucidating this appellation Śiva, Nīlakaṇṭha (Nilakantha) the commentator of Mahabharata observes —
atriḥ atrigotrāpatyatvād budhaḥ/ tena sarvagrahasvarūpītyarthaḥ.
While, according to Nīlakaṇṭha, atri may be taken to illustrate the quintessence of the celestial bodies of Budha (Mercury), Candra (Moon) and the other descendents of the Atri lineage, this name of Mahādeva (Mahadeva) Śiva can also be interpreted differently. The word atri is derived from the Sanskrit root ad. Ad refers to eating, devouring or consuming. From this sense atri referring to the one who consumes or devours corresponds to the all-engulfing fire. Both in the epics and Purāṇas (Puranas), Rudra-Śiva has been inseparably associated to Agni. Thus, atri is the other name for the blazing and fiery manifestation of Mahādeva Śiva.
Again, according to the ancient Śatapatha Brāhmaṇa (Shatapatha Brahmana) and Bṛhadāraṇyakopaniṣat (Bridarannyakopanishada), the term derived from the root ad is atti, whose other variation is atri. This atti or atri has been conceptualised in these texts as vāg (vaak or sentence/speech) or Vākya Saraswati (Vakya Saraswati). As a matter of fact, the vāgendriya (Vagendriya) or articulator and rasanā (rasana) or tongue (organ of taste) used in order to speak and express, may also be wielded to consume and engulf. Śatapatha Brāhmaṇa too attributes atri to vāg or speech, referring to the idea of earning sustenance through speech and expression —
vāgevātrīvārcā hi annaṃ/ hyannaṃ adyate
attirha vai nāmaitat yad atririti.
In the Sahasranāma Stotra, the hymn praising the thousand names of Śiva, Mahādeva has been referred to as Atri because among other reasons it also corresponds to speech. Atri can be further elucidated from another approach as well. Tri here refers to the three basic qualities or components – sattva (sattva), rajaḥ (rajas), tamaḥ (tamas) or triguṇa (triguna) — of creation. As Śiva corresponds indistinguishably to the Supreme Being or Brahma (Brahma), prevailing beyond triguṇa , he is called Atri.;