Are such gloves juvenile? (3)

I believe the answer is:

kid

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'juvenile?' is the definition.
(kid is a kind of juvenile)

I cannot understand how the rest of the clue works.

(Other definitions for kid that I've seen before include "Rib" , "Jest" , "Playfully deceive" , "A baby goat or informal child" , "Joke" .)

I've seen this clue in the Evening Standard.

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