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. (October 23, 2018). https://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/vasanas
"Vāsanās." The Concise Oxford Dictionary of World Religions. . Retrieved October 23, 2018 from Encyclopedia.com: https://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/vasanas