He was Poirot viscount strangely caught out (7)

I believe the answer is:

ustinov

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'he was poirot viscount strangely caught out' is the definition.
The definition suggests a singular noun which matches the answer.

This is the entire clue.

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(Other definitions for ustinov that I've seen before include "Peter . . . . . . ., late actor and raconteur" , "Sir Peter --, raconteur" , "See 22" , "British actor and playwright" , "past actor" .)

I've seen this clue in The Sun.

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