What word is the closest to qualia
I don't think there is any single word that's cleanly equivalent to qualia, but there are some that approach the idea from different angles.


  sabhāva-dhamma: Condition of nature; any phenomenon, event, property, or quality as experienced in and of itself.


sabhāva by itself means "own-being" or "own-becoming". It describes the intrinsic nature or essence of living beings.


  dhamma: (1) Event; a phenomenon in and of itself; (2) mental quality; (3) doctrine, teaching; (4) nibbāna. Also, principles of behavior that human beings ought to follow so as to fit in with the right natural order of things; qualities of mind they should develop so as to realize the inherent quality of the mind in and of itself.


dhamma by itself can describe a kind of mental quality or quality of thought.


  mūla: Literally, "root." The fundamental conditions in the mind that determine the moral quality — skillful (kusala) or unskillful (akusala) — of one's intentional actions (see kamma). The three unskillful roots are lobha (greed), dosa (aversion), and moha (delusion); the skillful roots are their opposites. See kilesa (defilements).


mūla describes the root of our actions; the quality of our intention behind them.

sabhāva-dhamma and dhamma probably come closest, while mūla carries the same concept but applies it very specifically to the mental root of action.