Advaryu is one of the four priests called ritviks who conduct yajna (a Vedic ritual) for yajamana (the sacrifice). Adhvara means yajna (a sacrifice). Adhvaryu is the officiating priest attached to Yajur Veda. There are other priests called hota, udgata, and Brahma. Brahma supervises the yajna attached to Atharva veda. Hotr recites the passages from Rig Veda and hence is called hotr and in Agnihotra offers oblations into the fire. The udgatr chants the hymns of Sama Veda. The adhvaryu, who performs the ritual has his own importance. He is the person who offers the oblations into the fire as per Vedic injunctions. Hota and Udgata may come in the middle and go when their part is over. But, adhvaryu remains from the beginning to the end. As success depends upon the performance of adhvaryu, he may be said to be pivotal to the yajna.
He should be a capable person who plans, well in advance, all his deeds, so that the yajna is successful. His commands are faithfully carried out by all the other priests. He decides the size and shape of the Vedic altar, the size and number of bricks to be used in accordance with the type and nature of yajna to be performed.
He uses his fingers to make certain gestures that have a great significance in a yajna. The adhvaryu is assisted by three priests, pratisthatr, nistr and unnetr. Three other priests assist him. They are savitri, vaikarta and camaradhvaryu.