RAF agitated with English submarine type? (10)

I believe the answer is:

anglerfish

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'submarine type?' is the definition.
Although both the answer and definition are singular nouns, I don't see how one could define the other.

'raf agitated with english' is the wordplay.
'agitated with' indicates an anagram.
'raf' with its letters anagrammed with 'english' gives 'ANGLERFISH'.

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I've seen this clue in The Times.

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