Vāsanās, from a root meaning to perfume, are the residues of past actions that scent the mind and dispose it to desire and act in certain ways. Vedānta and Yogācāra Buddhism both use the idea to explain how ignorance perpetuates itself. Liberation is often described as the wearing away of the vāsanās.
Vāsanā
A latent tendency: the subtle trace of past experience that colours perception and desire.
Also: Vasana