Like Andrew, happy as Larry (5)

I believe the answer is:

merry

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'like' is the definition.
Both the definition and answer are adjectives. Maybe there's a link between them I don't understand?

I cannot understand how the rest of the clue works.

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(Other definitions for merry that I've seen before include "Drunk - happy" , "Slightly intoxicated" , "Jolly and bright" , "Enlivened by drink" , "Joyous; tipsy (colloq.)" .)

I've seen this clue in the Evening Standard.

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