Sri Lanka on zero, England on top, royal massacre (9)

I believe the answer is:

slaughter

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'top royal massacre' is the definition.
'slaughter' can be an answer for 'massacre' (I've seen this before). I am unsure of the 'top royal' bit.

'sri lanka on zero england' is the wordplay.
'sri lanka' becomes 'slr' (I can't justify this - if you can you should give a lot more credence to this answer).
'on' means one lot of letters goes inside another (as in clothing \'on\' a person).
'zero' becomes 'aught' (synonyms).
'england' becomes 'e'.
'aught'+'e'='aughte'
'slr' enclosing 'aughte' is 'SLAUGHTER'.

'on' is the link.

Can you help me to learn more?

(Other definitions for slaughter that I've seen before include "Butchery" , "Murder" , "Wholesale killing" , "Kill cruelly" , "Killing (of farm animals)" .)

I've seen this clue in The Hindu.

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