1. In Hinduism, the underlying desires, memories, ambitions, etc., which form character, and which can surface at any moment. They are thus close to (sometimes synonymous with) saṃskāras(z).
2. In Buddhism, they contribute to the storehouse consciousness, ālaya-vijñāna.
"Vāsanās." The Concise Oxford Dictionary of World Religions. . Encyclopedia.com. (August 19, 2018). http://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/vasanas
"Vāsanās." The Concise Oxford Dictionary of World Religions. . Retrieved August 19, 2018 from Encyclopedia.com: http://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/vasanas