Crossword Genius

Repetition terribly irate on it (9)

Ross

I believe the answer is:

iteration

'repetition' is the definition.
(I know that iteration is a type of repetition)

'terribly irate on it' is the wordplay.
'terribly' indicates an anagram.
'irate'+'on'+'it'='irateonit'
'irateonit' with letters rearranged gives 'ITERATION'.

(Other definitions for iteration that I've seen before include "Repetition" , "Reprise" , "Repeating" , "Repeats" , "Repeated performing" .)

I've seen this clue in The Daily Express.
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