The sense impressions left by events, objects, experiences, on the mind. But also smell (Tamil. Vasanai). So Proustian. A mnemonic.
According to the doctrine of vāsanās - memory traces or smells - perception itself is half memory. One remembers because one sees a partial similarity between the object present and an object one has seen before. So one needs remembrancers so that one may remember, recognise - literally re-member or reconstitute the object in front of us - by reconnecting present impressions with past memories of that object.
from 'The Ring of Memory' by A.K.Ramanujan, Uncollected Poems and Prose, Delhi: OUP, 2001. Quoted by Niranjan Mohanty in 'Memory in the Poetry of A.K.Ramanujan: A Study', Kavya Bharti, Madurai: No. 17, 2005.