Asha (/ˈɑːʃə/; aša) is the Avestan language term (corresponding to Vedic language ṛta) for a concept of cardinal importance to Zoroastrian theology and doctrine. In the moral sphere, aša/arta represents what has been called "the decisive confessional concept of Zoroastrianism." The opposite of Avestan aša is druj, "lie."The significance of the term is complex, with a highly nuanced range of meaning.