While discussing the theory of illusory perception, this word is often used in Vedānta to denote the substratum wherein the illusion occurs. For instance, when a snake is perceived in a rope, or silver in nacre, the rope or the nacre forms the ‘adhiṣṭhāna’ or substratum, for this illusory perception. Ignorance of this adhiṣṭhāna causes the illusion and its true knowledge dispels it.
While enumerating the five causes responsible for the accomplishment of every action, the Bhagavadgītā (18.14) puts ‘adhiṣṭhāna’ as the first in the list. The word is interpreted there as the body, since the body is the primary basis necessary for all actions.
In works on Hindu Architecture including Temple Architecture, the word denotes the basement of a building or even a column. Innumerable varieties of the same are detailed in those works.
In Civics, the word was used to indicate a seat of administration like a city-council.