Some portions of the annapiṇḍa(s) (annapinda; food in the shape of a ball, used in sraddha-rituals) that are placed on kuśa (kusa; a king of grass), to be offered to the deceased spirit, are given to the Brāhmaṇa(s). Since Brāhmaṇa(s) partake of the anna, that portion of the anna is called anvāhāryaka (anwaharyaka).
yasmādannād dhṛtā mātrā bhakṣayanti dvijāytayaḥ.
anvāhāaryaka mityuktaṃ tasmattaccandrasaṃṣkaye.
This ritual is somewhat similar to the Vedic ritual paridhi-nikṣepa(paridhi-nikshepa). [See Śaṃyuvāk]

Anvāhāryaka according to Purāṇa (Purana; Mythological Scripture) is the anna related to śrāddha (sraddha), but in the Vedic era it was a general part of yajña 9yajna; fire-sacrifice). The food cooked for the yajña-performing Brāhmaṇa(s), during the days of yajña, was called anvāhārya. Since this anna was cooked in the flame of Dakṣināgni (Dakshinagni), another name for it was anvāhārya, and Dakṣhināgni was also known as anvāhārya-pacana. The container in which this food was cooked , was called anvāhārya-sthālī (anvwaharyaka-sthali).