The line between homa and the larger yajna is more a matter of scale and setting than a strict category difference: both center on offerings poured into consecrated fire while mantras are recited, but homa generally names the more modest, portable version performed in a small altar for domestic, therapeutic, or occasional purposes, in contrast to the elaborate, multi priest yajnas of the ancient royal and public tradition, and Hindu texts and communities do not draw a single uniform line between the two terms in every context.
Fire offering of this kind did not remain confined to Hinduism: as Buddhism developed its esoteric, tantric traditions in India and carried them into East Asia, the homa rite travelled with it, transmitted through China and taking root in Japan as the goma ritual central to Shingon and Tendai Buddhist practice, in which ordained priests still perform an elaborate fire offering directly descended from the Vedic homa despite belonging to an entirely different religion with its own distinct theology of what the fire and the offering accomplish. Tibetan Buddhist tradition preserves a parallel fire offering practice of its own, again derived from the same Indian tantric homa tradition through a separate line of transmission, so that a fire ritual with recognizably the same core structure, a consecrated fire, specific substances offered into it, and mantras carrying the offering to its intended recipient, survives today inside Hindu, and two distinct branches of Buddhist, ritual practice.