Sacrifices are considered to be the links between men and gods like Indra. Ahīna is one of the several kinds which come under the Soma group of sacrifices. It is a general nomenclature for all Soma sacrifices wherein the extraction of the soma juice is spread over several days. Hence the name ‘Ahīna,’ ‘that which takes several days to perform’.
An Ahīna is always begun on a full-moon day. The extraction of soma juice may be spread over 2 to 12 days. It should always end with an Atirātra (another Soma sacrifice spread over a day and night). Along with the dīkṣā (consecration of the sacrificer at the beginning) and upasad (another small sacrifice of the iṣṭi type) the whole sacrifice should not extend beyond a month.
The well-known Aśvamedha sacrifice belongs to the Ahīna group.