Salad of two eggs, thistle? Lose it (3,3,7)

I believe the answer is:

get the giggles

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'lose it' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'salad of two eggs thistle?' is the wordplay.
'two eggs' can mean two substitutions for 'egg'.
'salad of' indicates anagramming the letters.
'egg'+'egg'+'thistle'='eggeggthistle'
'eggeggthistle' is an anagram of 'GET THE GIGGLES'.

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I've seen this clue in The Everyman puzzle in The Observer.

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