Atharvan ( ; an n-stem with nominative singular ) was 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 yagna. Sometimes he is also reckoned among the seven seers or Saptarishi. His clan is known as the Atharvanas.
See more at Wikipedia.org...