One guzzles gallons, given thin bottle (6,4)

I believe the answer is:

greedy guts

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'one guzzles' is the definition.
I can't tell whether this definition defines the answer.

'gallons given thin bottle' is the wordplay.
'gallons' becomes 'g' (abbreviation).
'given' means one lot of letters go next to another.
'thin' becomes 'reedy' (as in a thin or reedy voice).
'bottle' becomes 'guts' (I've seen this before).
'g'+'reedy'+'guts'='GREEDY GUTS'

Can you help me to learn more?

(Other definitions for greedy guts that I've seen before include "Excessive eater" , "Pig" .)

I've seen this clue in The Times.

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