Crossword Genius

At Waterloo maybe nothing's lost after absolute end of Bonaparte (8)

Ross

I believe the answer is:

astatine

I'm a little stuck... Click here to teach me more about this clue!

'at' is the definition.
('astatine' can be a synonym of 'at')

I don't understand the remainder of the clue.

Can you help me to learn more?

(Other definitions for astatine that I've seen before include "radioactive material" , "Rare element" , "Atomic number 85" , "Chemical element At" , "Radioactive element" .)

I've seen this clue in The Independent.
Want a hint initially instead of a full solution? Install my app