Crossword Genius

In error, since I'm not all-knowing (10)

Ross

I believe the answer is:

omniscient

'all-knowing' is the definition.
('omniscient' can be a synonym of 'all-knowing')

'in error since i'm not' is the wordplay.
'in error' indicates anagramming the letters.
'since'+'im'+'not'='sinceimnot'
'sinceimnot' anagrammed gives 'OMNISCIENT'.

(Other definitions for omniscient that I've seen before include "All-knowing" , "Knowing everything" .)

I've seen this clue in The Telegraph.
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