Adhyāsa (Sanskrit:अध्यास Superimposition) is a concept in Hindu philosophy referring to the false superimposition of an attribute, quality, or characteristic of one entity onto another entity. In Vedanta, Adhyasa means a false superimposition of the characteristics of physical body (birth, death, skin color etc.) onto the Atman, and also the false superimposition of the characteristics of Atman (sentiency, existence) onto the physical body.

The first mention of Adhyasa is found within the Brahma Sutra Bhasya of Adi Shankara. Adi Shankara begins his commentary of the Brahma Sutras by explaining what Adhyasa is and it's nature.

Shankara lists different views about Adhyasa from different philosophical schools, which proves that the concept of Adhyasa certainly existed before Shankara.