Crossword Genius

Train Henry to swim in a sea (10)

Ross

I believe the answer is:

tyrrhenian

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'a sea' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'train henry to swim' is the wordplay.
'to swim' indicates anagramming the letters.
'train'+'henry'='trainhenry'
'trainhenry' is an anagram of 'TYRRHENIAN'.

'in' acts as a link.

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I've seen this clue in The Independent.
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