Booster's inside, left on ice (5)

I believe the answer is:

tonic

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'booster's' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Perhaps they are linked in a way I don't understand?

'inside left on ice' is the wordplay.
'inside' indicates a hidden word.
'TONIC' is hidden in the letters of 'left on ice'.

Can you help me to learn more?

(Other definitions for tonic that I've seen before include "Invigorating drink" , "Accompaniment to gin?" , "Keynote of a scale" , "Carbonated mixer" , "medicinal preparation" .)

I've seen this clue in The Daily Mail.

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