Explode or shatter outright (5)

I believe the answer is:

burst

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This clue could be a double definition.

'explode' is the first definition.
(synonyms)

'shatter outright' is the second definition.
'burst' can be an answer for 'shatter' (synonyms). I am not certain of the 'outright' bit.

'or' is the link.

Can you help me to learn more?

(Other definitions for burst that I've seen before include "Explosion" , "Rupture" , "Blowout" , "Ruptured" , "Suddenly break open" .)

I've seen this clue in the Evening Standard.

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