Atharvan

Atharvan (अथर्वन्, '; an n-stem with nominative singular अथर्वा ') is a legendary Vedic sage (rishi) of Hinduism, who along with Angiras, is supposed to have authored ("heard") the Atharvaveda. He is also said to have first instituted the fire-sacrifice or yajña. Sometimes he is also reckoned among the seven seers, the Saptarishi. His clan is known as the Atharvanas. Atharvan married Shanti, daughter of Prajapati Kardama, and had a great sage Dadhichi as a son. He is referred to as a member of the Bhrigu clan.

According to the Mundaka Upanishad and other texts, he was the eldest son and (Manasaputra) born from mind of the creator deity, Brahma.

Etymology
Vedic atharvan is cognate with Avestan āθrauuan / aθaurun, "priest", but the etymology of the term is not yet conclusively established. It was once thought to be etymologically related to the Avestan ātar, but that is now considered unlikely (Boyce, 2002:16). It has been suggested by scholars that the Vedic and Avestan terms are not of Indo-European origin, and are derived from the BMAC substrate.