More than one plain kid utterly rejected (6)

I believe the answer is:

llanos

'more than one plain' is the definition.
(llano is a type of South American plain)

'kid utterly rejected' is the wordplay.
'kid' becomes 'son' (male child).
'utterly' becomes 'all' (I've seen this in another clue).
'rejected' says the letters should be written backwards.
'son'+'all'='sonall'
'sonall' reversed gives 'LLANOS'.

(Another definition for llanos that I've seen is " Grassy plains in South America".)

I've seen this clue in The Guardian.

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