Rough player in childish attire (6)

I believe the answer is:

romper

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'rough player in childish attire' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe there's a link between them I don't understand?

This is all the clue.

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(Other definitions for romper that I've seen before include "Young child's one-piece outer garment" , "Child's onesie" .)

I've seen this clue in The Daily Express.

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