Childish place to put food and drink (3)

I believe the answer is:

tum

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'drink' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.

I can't explain the remainder of the clue.

Can you help me to learn more?

(Other definitions for tum that I've seen before include "Stomach (informal)" , "Belly" , "Middle" , "Corporation" .)

I've seen this clue in the Evening Standard.

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