In Hinduism, Adhvan is a term with different meanings in knowledge texts. The term adhvan is connected with adhvara. It is related to the nominal stem adh (water), originally meaning ‘watery course’, and the term adhvara originally meant, primarily, a conveyance to go on water or a boat, and secondarily, ‘sacrifice’. In Sanskrit,it is adhvan, in Pali, addhan, and in Prakrit, addha, addhana.
The term adhvan in Samhitas means ‘course, road, path’ (Rig Veda 1.23.6;10.22.4, etc), and also, journey, walk (Rig Veda 1.42.8); in Brahmanas and Upanishads it also denotes ‘trans-migratory journey’ (Taittirya Brahmana 2.4.6.4; Katha Upanishad 3.9., etc.). In Upanishads the knowledge of the all important esoteric doctrine is compared with a means of transport enabling a person to go over a long distance (Brihadaranyaka Upanishad 4.2.1), as well as the journey to the supreme abode, brought to an end by the person who has the right insight and control over the mind and the senses (Katha Upanishad 1.3.9). In Tantra texts, the term also denotes the ‘six-fold pathway of spiritual progress’ (considered as the modes of manifestation of the deity) (Mrgendra Tantra 1.1.2.4; Malini Tantra 2.52). In astronomical texts, the term denotes ‘longitudinal distance of a place from the prime meridian’. It also stands for ‘house in the horoscope’ (Taji Nikaya 1 (3). 61 (122). In Buddhist texts, the term stands for ‘course of time, time or state (past, present and future)’ (Abhidhamma Kosha 1.7). In metrics, the term denotes ‘possible combination of short and long syllables’. Sometimes, the term is used for ‘place in the order of counting’ (Sainskaraprakasa 883.16).
The basic meaning of the term adhvan is ‘course, road, path’, and it is connected with adhvara, ‘path or vehicle whereby the gods come to the yajamanas dwelling.’ In the ritual spheres, adhvan could convey the way leading the yajamana to the heavenly region.