Irritated re thin, veritable, prince of Moscow (4,3,8)

I believe the answer is:

ivan the terrible

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'prince of moscow' is the definition.
The definition suggests a singular noun which matches the answer.

'irritated re thin veritable' is the wordplay.
'irritated' indicates anagramming the letters (I've seen this in other clues).
're'+'thin'+'veritable'='rethinveritable'
'rethinveritable' anagrammed gives 'IVAN THE TERRIBLE'.

Can you help me to learn more?

(Other definitions for ivan the terrible that I've seen before include "despot" , "Old ruler" , "Dreadful ruler" , "Dictator" , "First tsar of all Russia" .)

I've seen this clue in the Sydney Morning Herald.

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