Diarist insult (anag) – tycoon (13)

I believe the answer is:

industrialist

(Other definitions for industrialist that I've seen before include "Ford, perhaps" , "Tycoon" , "Businessman - I trail nudists (anag)" , "Manufacturing magnate" , "Businessman - distrust in Ali (anag)" .)

I've seen this clue in The Guardian.

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