Agnihotra is a tatpuruṣa compound (samāsa), meaning an offering (originally, of milk) into Agni (Latin ignis, etc.) or consecrated fire. It finds earliest mention in the Atharva Veda (1000 BC), vi 97,1, (source Monier Williams) though pouring into the ritual fire was known as early as in the Ṛgveda (c. 1400 BC) and it the closely related Zoroastrian religion (Yasna Haptaŋhāiti). There is a simplied version of the Agnihotra in the Grihyasutras and in later post-Vedic texts.