Very large drink - dry liqueur (6,3)

I believe the answer is:

triple sec

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'liqueur' is the definition.
(triple sec is a kind of liqueur)

'very large drink dry' is the wordplay.
'very large drink' becomes 'triple' (I can't justify this - if you can you should give a lot more credence to this answer).
'dry' becomes 'sec' (similar in meaning).
'triple'+'sec'='TRIPLE SEC'

Can you help me to learn more?

(Other definitions for triple sec that I've seen before include "Drink" , "Strong orange-flavoured liqueur - perils etc (anag)" , "alcohol" .)

I've seen this clue in The Daily Express.

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